Recent research has confirmed 
traditional herbal knowledge, proving that the herb has  
a remarkable ability to protect the liver from damage 
resulting from alcoholic and other types of poisoning. Today, milk thistle is widely used in the West for the 
treatment of a range of liver conditions. Tablets  are prescribed for long-term treatment of liver disorders.Spiny, thistle- 
like leaves are 
gray-green
Seeds contain silymarin, 
which protects the liver. They are the main part 
used in remedies. Flower heads  are eaten as a tonic 
food and can be used in remedies. Fresh flower 
head
Dried flower 
head
Seeds
US_136-137_Serenoa_Silybum.indd   137 26/02/16   4:00 pm
138Symphytum officinaleKey Medicinal plants
Aerial parts are rich 
in anti-inflammatory and astringent substances. Root is harvested in autumn when the allantoin levels are highest. Infused oil of leaves 
(to make, p. 294). Apply to sprains. Chopping leaves  For boils, apply as a poultice (see p. 295). Ointment of leaves  (to make, p. 295). Apply to bruises. Symphytum officinale (Boraginaceae)
Comfrey, Knitbone
Comfrey’s names testify to its traditional use in mending 
broken bones. “Comfrey” is a corruption of con firma, meaning the bone is “made firm,” Symphytum is derived from the Greek for “to unite,” and knitbone speaks for itself. Comfrey is also a wound herb. K’Eogh in his Irish Herbal (1735) wrote that it “heals all inward wounds and ruptures.” Today, it is still highly regarded for its healing properties. Habitat & Cultivation
An indigenous European plant, 
comfrey grows in all temperate regions of the world, including western Asia, North America, and Australia. It thrives in moist, marshy places. It can be grown from seed in spring or by root division in autumn, and the leaves and flowering tops  are harvested in summer. The root  is unearthed in autumn. Key Constituents
■ Allantoin (up to 4.7%)
■ Mucilage (about 29%)
■ Triterpenoids
■ Phenolic acids  
 (rosmarinic acid)
■ Asparagine
■ Pyrrolizidine alkaloids  
 (0.02–0.07%)
■ Tannins 
Key Actions
■ Demulcent
■ Astringent
■ Anti-inflammatory
■ Heals wounds and bonesResearch
■ Active constituents Allantoin  
is a cell-proliferant that stimulates  the repair of damaged tissue. The herb’s anti-inflammatory activity  is partly due to the presence of rosmarinic acid and phenolic acids. ■ Pyrrolizidine alkaloids 
Research shows that, as isolated substances, certain pyrrolizidine alkaloids can be highly toxic to the liver. It is still unclear whether they are toxic in the context of the  whole plant, as they are only present in minute amounts, often being completely absent from samples  of dried aerial parts. The highest concentration is in the root, which should not be used internally. Skin applications, as well as the aerial parts of the plant, are considered safe. ■ Clinical research In Germany  
and elsewhere in Europe, comfrey  
is widely used for sprains, bruises,  
and sports injuries. Research, mostly  
in Germany, endorses the traditional knowledge of comfrey’s wound-healing ability. In a 2007 study, physicians rated the efficacy of a comfrey leaf cream in healing abrasions. The doctors rated its effectiveness as good or very good  in 93% of cases, and complete healing took 4 days with comfrey and 7 days with placebo. Other studies indicate comfrey’s value in promoting tissue repair and as an anti-inflammatory  in conditions such as sprained ankle, osteoarthritis, and lower back pain. Traditional &  
Current Uses
■ Injuries Comfrey’s ability to 
promote the healing of bruises, Comfrey
A perennial growing  to 3 ft (1 m), with  thick leaves and bell-like white to pink  or mauve flowers. sprains, fractures, and broken bones 
has been known for thousands of years. It encourages ligaments and bones to knit together firmly. A comfrey compress applied immediately to a sprained ankle can significantly reduce the severity of the injury. The combination of tannins and mucilage helps to soothe bruises and grazes. ■ Other uses Comfrey preparations 
have many other uses and can be Comfrey was known to the Greek physician 
Dioscorides in the 1st century ce, who wrote about it in his Materia Medica. Parts Used
Key Preparations & Their Uses
applied to heal problems such as 
insect bites, scars, skin inflammation, acne, and mastitis. Self-help Uses
■ Acne & boils, p. 305. ■ Fractures, p. 312. ■ Fungal skin infections, p. 304. ■ Healing wounds, p. 304. ■ Inflamed skin rashes, p. 303. ■ Stiff & aching joints, p. 313. QCautions Do not use on dirty wounds as rapid healing can trap dirt or pus. T ake internally only under professional supervision. Restricted in some countries. Do not take during pregnancy or while breastfeeding.Fresh root
Dried rootFresh  
aerial parts
Dried  
aerial parts
Tincture of root (to make, p. 292). Apply undiluted to acne. US_138-139_Symphytum_Tabelula.indd   138 26/02/16   4:00 pm139Tabebuia  spp .Key Medicinal plants
Habitat & Cultivation
An indigenous South American tree, 
pau d’arco grows well in mountainous 
terrains. In Peru and Argentina it is 
found growing high up in the Andes. Pau d’arco is also found in low-lying 
areas (in Paraguay and Brazil), where 
it is thought to have originated. Many 
Tabebuia  species are used in herbal medicine, so quality control of dried 
bark can be difficult. T. avellanedae   
is considered to be the most 
therapeutic ally effective species, 
while T. impetignosa  is the species  
that is most commonly available. Pau d’arco is not normally 
cultivated—the prized inner bark is 
collected from trees growing in the 
wild, throughout the year. Key Constituents
■ Napthaquinones (lapachol)
■ Anthraquinones
■ Coumarins
■ Flavonoids
■ Iridoids
■ Carnosol
Key Actions
■ Antibacterial
■ Antifungal
■ Antiparasitic
■ Immunostimulant
■ Anti-inflammatoryPau d’arco
An evergreen tree 
(deciduous in cold 
climates) reaching  
100 ft (30 m), with 
pink flowers. ■ Tonic
■ Antitumor
Research
■ Antibacterial and antifungal 
activity  A Colombian review (2013) 
of research data on Tabebuia  species, 
much of which was undertaken  
in South America, highlighted pau 
d’arco’s strong, direct activity against 
several key bacteria, notably 
Staphylococcus aureus  and 
Helicobacter pylori , the latter being 
the principal cause of stomach ulcers. It also has broad-ranging activity 
against many fungal agents, including 
Candida albicans . ■ Antitumor properties  Pau 
d’arco’s anticancer action has been 
established in laboratory 
experiments, with many of its 
constituents suppressing the growth 
of cancer cells. Research in Brazil in 
the 1960s raised great hopes that 
pau d’arco might prove to be a major 
cancer treatment, but clinical 
research has failed to produce 
positive results. Traditional & 
Current Uses
■ Early cure-all  The Incas, the 
Callawaya in Brazil, and other Native 
South American peoples all prized  
pau d’arco as a cure-all. They used  
it to treat a variety of conditions, Pau d’arco  is valued for its durable wood  
and for its bark that has important 
therapeutic properties.including wounds, fever, dysentery,  
and intestinal inflammation, as well as 
certain types of cancer and snake bite. ■ Infections  Given the large 
number of active constituents in  
pau d’arco, it is not surprising that  
this beneficial herb is used in South 
America and by herbal practitioners 
throughout the world. It is an 
important, natural antibiotic for 
bacterial and viral infections, 
especially of the nose, mouth, and 
throat, and is considered helpful for 
chronic conditions such as CFS 
(chronic fatigue syndrome). Pau d’arco is also used for fungal 
conditions, including ringworm and 
thrush, and is considered especially 
useful for treating chronic candidiasis. ■ Anti-inflammatory action  
Pau d’arco reduces and relieves 
inflammatory problems, especially  
in the stomach and intestines. It  
is used to treat a wide range of  
other inflammatory conditions, 
including cystitis, inflammation of  
the cervix, and prostatitis. ■ Cancer remedy  Clinical 
experience in Brazil, combined  
with its worldwide use by herbalists 
as a cancer remedy, suggests that  
pau d’arco may be beneficial in  
the treatment of cancer, including 
leukemia. However, more intensive 
research is needed into its 
therapeutic value. QCaution If taking anticoagulant medication, take pau d’arco only on professional 
advice. Do not take during pregnancy. Avoid if trying to conceive.Tabebuia spp. (Bignoniaceae)
Pau d’Arco (Portuguese), Lapacho (Spanish)
Bark from the pau d’arco tree has been valued  
for centuries in traditional South American herbal 
medicine for its remarkable health benefits. Today,  
it is given as a remedy for inflammatory and infectious 
problems, including conditions such as chronic fatigue 
and candidiasis. It is also used for other conditions and 
has a mixed reputation as a treatment for cancer, 
including leukemia. Tincture  (to make, p. 292) is 
suitable for long-term use. For cfs, take 40 drops with 
water 3 times a day.Decoction  (to make,  
p. 291) is a traditional 
preparation in South 
America. For candidiasis, 
drink 3/4 cup (150 ml)  
3 times a day.Parts Used Key Preparations & Their Uses
Dried inner barkInner bark  is prized for its immunostimulant properties. It is used to treat many inflammatory conditions. Bark has important 
antibiotic properties
Ointment  (to make, p. 295). For wounds, apply freely. US_138-139_Symphytum_Tabelula.indd   139 26/02/16   4:00 pm
140Tanace Tum par TheniumKey medicinal plants
Fresh leaves To prevent  
migraine, eat 2–3 leaves 
daily on a piece of bread.Tincture (to make, p. 292). For  
long-term prevention of migraine,  
take 10 drops a day.The leaves contain 
parthenolide, which 
helps prevent migraineTanacetum parthenium (Asteraceae)
FeverfewFeverfew
An herbaceous perennial growing  to 2 ft (60 cm), with numerous daisylike flower heads. Feverfew has daisylike flowers that bloom  
all summer. Habitat & Cultivation
Originally from southeastern 
Europe, feverfew is now common throughout Europe, Australia, and North America. It can be propagated from seed or cuttings, and prefers well-drained soil and sun. The leaves are picked as required and the aerial parts as a whole are harvested in summer when the plant is in flower. Related Species
Feverfew is a close relative of  
tansy (Tanacetum vulgare, p. 274),  and the chrysanthemum and chamomile species. Key Constituents
■ Volatile oil (alpha-pinene)
■ Sesquiterpene lactones  
 (parthenolide)
■ Sesquiterpenes (camphor)
Key Actions
■ Anti-inflammatory
■ Analgesic
■ Reduces fever
■ Antirheumatic
■ Promotes menstrual flowResearch
■ Migraine When, in 1973, the wife 
of a Welsh doctor ended her 50- year history of migraine with  a course of feverfew, a detailed scientific investigation got underway. In clinical trials in Britain during the 1980s the herb was shown to be an effective remedy for migraine. Further clinical trials across Europe, including one in 2006 that combined feverfew and willow bark (Salix alba, p. 129), attest to feverfew’s ability to treat migraine. The trials indicate feverfew may need to be taken long term (for 6 months or more) for full effect. ■ Rheumatoid arthritis 
Feverfew’s effectiveness in the treatment of rheumatoid arthritis  is being investigated. Traditional &  
Current Uses
■ Fevers  As its name implies, 
feverfew may be used to lower 
temperature and cool the body. ■ Gynecological uses The herb 
has been used since Roman times  
to induce menstruation. It is also  
given in childbirth to aid expulsion  
of the placenta. ■ Migraine & headaches In small 
quantities, feverfew is now used as a preventative for migraine. It has to be taken regularly, and at the first signs of an attack. It is useful for migraine associated with menstruation, and  for headaches. ■ Arthritis remedy The herb  
can help arthritic and rheumatic  
pain, especially with other herbs. Self-help Use
■ Migraine prevention, p. 309. Parts Used
Key Preparations & Their UsesAerial parts  
are harvested in summer when the plant is in flower. Fresh aerial partsFeverfew’s main traditional use was as a woman’s 
herb. Nicholas Culpeper in The English Physitian  
(1652) sings its praises as “a general strengthener of [the] womb ... it cleanseth the womb, expelleth the after-birth and doth the woman all the good she can desire of an herb.” Feverfew is now used principally as a treatment for migraine, but has also long been thought of as an herb for arthritis and rheumatism. Cautions Eating fresh leaves may cause mouth ulcers. Do not take feverfew  
if taking warfarin or other blood-thinning drugs. Do not take during pregnancy. Can cause allergic reactions in rare cases.Dried  
aerial parts
Tablets often contain other herbs. T ake for headaches.Capsules (to make, p. 292). For symptomatic relief of headaches  
take a 100 mg capsule daily. US_140-141_Tanacetum_Taraxacum.indd   140 26/02/16   4:00 pm141Taraxacum officinaleKey medicinal plants
Tonic salad  made with dandelion leaves. Eat regularly for its cleansing benefits.Tablets  have a diuretic effect. T ake for fluid retention.Root  is harvested after  
2 years and is dried or roasted. Tincture  of root (to make, p. 292). For eczema, take 1⁄2 tsp diluted with  
1⁄2 cup (100 ml) water 3 times a day.Leaves contain  
high levels of 
potassium
Marigold petals Borage flowersTaraxacum officinale (Asteraceae)
Dandelion
Habitat & Cultivation
Dandelion grows wild in most parts 
of the world and is cultivated in 
Germany and France. It is propagated 
from seed in spring. The young leaves 
are picked in spring for tonic salads, 
and later as a medicine. The root  
of 2-year-old plants is unearthed  
in autumn. Related Species
Pu gong ying  (T. mongolicum ) is used  
in Chinese herbal medicine to “clear 
heat” and relieve toxicity, especially  
of the liver. Key Constituents
■ Sesquiterpene lactones
■ Triterpenes
■ Polysaccharides 
Leaf only:
■ Coumarins
■ Carotenoids
■ Minerals (especially potassium)
Root only:
■ Taraxacoside
■ Phenolic acids
■ Minerals (potassium, calcium) Key Actions
■ Diuretic
■ Detoxifying
■ Bitter
Research
■ Leaves  Research published in  
the journal Planta Medica , in 1974, 
confirmed that dandelion leaves  
are a powerful diuretic, though  
their exact mode of action is not 
understood. Many other small-scale 
studies have confirmed this diuretic, 
or more accurately, aquaretic effect 
of dandelion leaf. Aquaretic refers  
to the fact that many herbal diuretics 
stimulate just the elimination of 
water and potassium. As dandelion 
leaf has very high levels of potassium, 
it is thought that no net loss of this 
mineral occurs on taking the leaf. ■ Root  A 2004 laboratory study 
reported dandelion root had marked 
anticancer activity. It significantly 
increased tumor necrosis factor and 
apoptosis (programmed cell death). Traditional & 
Current Uses
■ Diuretic  Dandelion leaf is used  
as a diuretic and treats high blood 
pressure by reducing the volume  
of fluid in the body. ■ Detoxifying remedy  Dandelion 
root is a key detoxifying herb that 
gently stimulates the liver and gall 
bladder’s capacity to clear waste 
products from the body. This action 
makes it valuable in the many health 
conditions that involve chronic toxicity, 
whether this toxicity is linked to 
inflammation, infection, or dietary or 
environmental factors. The root is 
typically taken to treat constipation, Dandelion
A perennial growing 
to 20 in (50 cm), 
with ragged basal 
leaves, hollow stalks, 
and golden flowers. skin problems, such as eczema, and 
arthritic conditions, where improved 
clearance of waste products can 
reduce local inflammation. ■ Other uses  Dandelion root is a 
good prebiotic, supporting the health 
of the gut flora. It has traditionally 
been used in the early stages of type 2 
diabetes, stimulating insulin release Dandelion’s  name, which is a corruption of 
the Latin dens leonis,  meaning“lion’s teeth,” 
derives from the appearance of its flowers.Parts Used
Key Preparations & Their UsesLeaves are juiced, eaten raw in salads, 
or dried for use in herbal preparations. from the pancreas and supporting 
stable blood-sugar levels. Self-help Uses
■ Acne & boils , p. 305. ■ Constipation , p. 307. ■ Detoxification for hangover , p. 309. ■ Fluid retention , p. 315. ■ Hives , p. 303.Known principally as a weed, dandelion has an astonishing 
range of health benefits. In Western folk medicine, the 
leaves, which can be eaten in salads, have long been used 
as a diuretic. They were recommended in the works  
of Arab physicians in the 11th century, and in an herbal 
written by the physicians of Myddfai in Wales in the 
13th century. The root, which has a shorter history  
of medicinal use, is good for the liver. Dried rootFresh root
Fresh leavesDried leaves
Juice made from leaves. For fluid retention, take 1 tbsp 3 times a day.Infusion  of leaves (p. 291). For swollen ankles, take 2 cups (500 ml) daily.Decoction  of root (p. 291). For acne, take 1⁄3 cup (75 ml) 3 times a day. US_140-141_Tanacetum_Taraxacum.indd   141 26/02/16   4:00 pm
142Terminalia arjunaKey medicinal plants
Bark is used to treat 
heart disease in IndiaTerminalia arjuna (Combretaceae)
ArjunArjun
An evergreen tree reaching 100 ft (30 m), with pale yellow flowers and cone-shaped leaves. Arjun is a handsome evergreen tree. Its 
bark is prescribed to help heart and circulation problems. Habitat & Cultivation
Arjun is found throughout most  
of the Indian subcontinent, from  Sri Lanka to the foothills of the Himalayas. It thrives in wet, marshy areas and on riverbanks. The tree is grown from seed and the bark  is cut in late winter. Related Species
A number of other Terminalia species are also used medicinally, notably beleric myrobalan and chebulic myrobalan (T. belerica and T. chebula,  p. 275). Both are close relatives of arjun and are among the most used herbal medicines in India. Key Constituents
■ Tannins
■ Triterpenoid saponins
■ Flavonoids
■ Phytosterols
Key Actions
■ Cardiac tonic
■ Lowers blood pressure
■ Reduces cholesterol levelsResearch
■ Cardiac tonic Research has  
been going on into arjun in India  
since the 1930s. The results have been highly conflicting, with some studies indicating that it increases heart rate and blood pressure, and others suggesting the reverse. It seems that the herb is best used  
to treat conditions where the blood supply to the heart is poor, for example in ischemic heart disease and angina. In a 2002 clinical trial  in India, 58 men with angina were given arjun. Results were very positive, with those taking arjun experiencing a marked reduction  in angina symptoms and an increased capacity to exercise. ■ Cholesterol Indian research has 
demonstrated that arjun reduces blood cholesterol levels. Traditional &  
Current Uses
■ Traditional heart remedy  
In Indian herbal medicine, arjun has 
always been taken as a heart tonic. It has a long history of treating heart failure and edema (a condition in which fluid accumulates in the ankles and legs because the heart is not pumping adequately). ■ Ayurvedic medicine Ayurvedic 
physicians use arjun to restore balance when any of the 3 humors, kapha, pitta, or vata  (see p. 37), is present in 
excess. As a decoction, the bark is given to treat diarrhea and dysentery. Powdered bark is part of a traditional Ayurvedic treatment for asthma. Arjun is also given in Ayurveda for bile duct problems, as well as for poisoning and scorpion stings. ■ Modern heart remedy Arjun is 
beneficial for angina and poor coronary circulation. It is also of benefit if the heart’s rate and rhythm are abnormal. By lowering blood cholesterol levels, Parts Used
Key Preparations 
& Their UsesDried  
bark
reducing blood pressure, and 
supporting normal heart function, arjun improves the health of the circulation and reduces the risk of developing a serious heart problem. Powder  is a traditional 
Ayurvedic remedy, 
prescribed for asthma. Decoction is used by herbalists to 
treat poor circulation to the heart.Tincture is a valuable cardiac tonic. Herbalists prescribe it to treat angina.The bark of the arjun tree has been used in Indian 
herbal medicine for at least 3,000 years, and has  
always been valued as a remedy for the heart. The  first person credited with prescribing arjun for heart disease was Vagbhata, an Indian physician of the  
7th century ce. Arjun is an example of an herb for  
which the traditional use has been confirmed by modern pharmacological research. QCaution T ake only under professional supervision.Bark has constituents that 
lower blood pressure and 
reduce cholesterol levels. US_142-143_Terminalia_Thymus.indd   142 26/02/16   4:00 pm143Thymus vulgarisKey medicinal plants
Leaves have 
an aromatic, 
bitter tasteThymus vulgaris (Lamiaceae)
Thyme, Garden Thyme
Habitat & Cultivation
Thyme is a cultivated variety of the 
wild thyme ( T. serpyllum , p. 276) of 
southern Europe and is now grown 
worldwide. It is raised from seed or 
by root division in spring and prefers 
light, chalky soils. The aerial parts are 
harvested in summer. Related Species
There are many Thymus  species, each 
with a different volatile oil content. Wild thyme ( T. serpyllum , p. 276) is 
often used in the same way as thyme. Key Constituents
■ Volatile oil (mostly thymol  
 and carvacrol)
■ Flavonoids
■ Phenolic acids
Key Actions
■ Antiseptic
■ Tonic
■ Relieves muscle spasms
■ Expectorant
■ Expels worms
■ AntioxidantResearch
■ Volatile oil  Thyme’s volatile oil is 
strongly antiseptic—the constituent 
thymol, in particular, is a most 
effective antifungal. The oil is also 
expectorant and it expels worms. ■ Anti-aging  Research in the 1990s 
in Scotland suggests that thyme and its 
volatile oil have a markedly tonic 
effect, supporting the body’s normal 
function and countering the effects  
of aging. More recent research 
indicates that thyme is strongly  
anti oxidant and may help maintain 
higher levels of essential fatty acids 
within the brain. ■ Stomach ulcers  Extracts of  
the herb have shown strong 
antibacterial activity against H. pylori , 
a bacterium often associated with 
stomach ulcers. ■ Menstrual pain  Many compounds 
within thyme relieve muscle cramps. A 2014 Iranian clinical trial compared 
the ability of thyme and ibuprofen  
to relieve period pains. The findings 
showed both treatments to  
be effective. Traditional &  
Current Uses
■ Infections  The antiseptic and  
tonic properties of thyme make it a 
useful tonic for the immune system in 
chronic, especially fungal, infections, as 
well as an effective remedy for throat 
and chest infections. ■ Asthma & hay fever  Thyme  
is prescribed with other herbs for 
asthma, especially in children. Its 
invigorating qualities balance the 
sedative effect of many herbs used  
for asthma. Thyme is also helpful  
in hay fever.Thyme
An aromatic shrub 
growing to 16 in  
(40 cm), with woody 
stems, small leaves, 
and pink flowers. ■ Worms  Thyme is often used to 
treat worms in children. ■ External uses  Applied to the 
skin, thyme relieves bites and stings, 
and is used for sciatica and rheumatic 
pains. It helps ringworm, athlete’s foot, 
thrush, and other fungal infections, 
as well as scabies and lice. Thyme 
infusion and diluted oil are also 
massaged into the scalp to encourage 
hair growth and reverse hair loss.Thyme’s pink flowers attract bees in 
profusion and give a distinctive flavor  
to the honey.Parts Used
 Key Preparations 
& Their UsesAerial parts , harvested in summer, 
contain antiseptic volatile oil. Dried aerial partsFresh leaves
Fresh aerial parts
Self-help Uses
■ Allergic rhinitis , p. 300. ■ Back pain , p. 313. ■ Bites & stings , p. 303. ■ Colds & flu , p. 311. ■ Coughs & bronchitis , p. 310. ■ Earache , p. 312. ■ Fungal infections , pp. 304 & 314. ■ Maintaining vitality , p. 319. ■ Mild asthma , p. 301. ■ Tired & aching muscles , p. 312.Syrup  (to make,  
p. 293) is a traditional 
cough remedy. T ake  
1 tbsp 3 times a day.Essential oil  for acne, 
dilute to 5% and dab 
onto inflamed spots.Infusion  (to make, p. 291). For colds, take 1/2 cup  
(100 ml) 3 times daily.Thyme was praised by the herbalist Nicholas Culpeper 
(1616–1654) as “a notable strengthener of the lungs,  
as notable a one as grows; neither is there a better 
remedy growing for that disease in children which they 
commonly call chin-cough [whooping cough].” Thyme is 
an excellent antiseptic and tonic, and today it is still used  
as a respiratory remedy, as well as being important for a 
variety of other ailments. QCautions  Do not take the essential oil internally. Do not use the essential oil externally during pregnancy. Tincture  (to make, p. 292). For thrush, apply 40 drops, 2–3 times daily. US_142-143_Terminalia_Thymus.indd   143 26/02/16   4:00 pm
144Turnera diffusaKey medicinal plantsTurnera diffusa syn. T. diffusa var. aphrodisiaca (Passifloraceae)
DamianaDamiana
An aromatic shrub growing to 6
1⁄2 ft (2 m), 
with smooth, pale green leaves and small, single yellow flowers. Damiana is an excellent tonic herb for 
physical weakness and nervous exhaustion. Habitat & Cultivation
Damiana is native to the Gulf of 
Mexico, southern California, the northern Caribbean Islands, and Namibia. It is also cultivated in these areas. Damiana is grown from seed  in spring and prefers a hot, humid climate. The leaves are harvested when the herb is in flower  in summer. Related Species
T. opifera and T. ulmifolia are used  as tonics in Brazil and Central America, respectively. Key Constituents
■ Volatile oil (about 0.5–1%),  
 including caryophylene,   thymol, and cadinene
■ Flavonoids
■ Hydroquinones (arbutin)
■ Tannins
Key Actions
■ Tonic
■ Nerve tonic
■ Aphrodisiac
■ Mild stimulant■ Mild antidepressant
■ Mild laxative and diuretic
Research
■ Initial research The first  
study into the aphrodisiac activity  of damiana (published in 1999)  found that male rats with low  sexual activity became more  sexually active when given damiana extract. One cannot generalize  
from animals to humans, but this  
does correspond with traditional views of the herb. Other recent research suggests that damiana  helps to prevent raised blood-  
sugar levels in diabetics. Traditional &  
Current Uses
■ T onic Damiana is a tonic and 
restorative for the nervous system, 
and has always been considered an aphrodisiac. Its tonic action is partly due to the constituent thymol, which is antiseptic and tonic. ■ Antidepressant Technically, 
damiana is a thymoleptic (having a stimulating action on the body and mind). It is given to people suffering from mild to moderate depression or nervous exhaustion. Its stimulating and restorative properties make it valuable when anxiety and depression happen together. ■ Sexual restorative Due to its 
reputed testosterogenic activity, damiana has always been seen as  an herb for men, helpful in treating premature ejaculation and impotence. It is, however, beneficial for both men and women, being considered restorative to the reproductive organs of both sexes. ■ Gynecological problems 
Damiana is often given for painful and delayed periods, and is used specifically for headaches connected to menstruation. ■ Urinary antiseptic Being a 
diuretic and urinary antiseptic, damiana is useful in the treatment of urinary infections such as cystitis and urethritis. This action is partly due to the constituent arbutin, which is converted into hydroquinone, a strong urinary  Parts Used
Key Preparations  
& Their UsesLeaves are harvested  
in summer. They make a pleasant-tasting tea and  are used for a wide range  of medicinal preparations. antiseptic, in the urinary tubules. This 
constituent is also found in a number of other plants, notably uva-ursi (Arctostaphylos uva-ursi, p. 170). ■ Laxative Damiana is a mild 
laxative, useful in the treatment of constipation due to poor bowel muscle tone. Self-help Use
■ Anxiety, depression, &  
 tension, p. 308.Tincture (to make, p. 292) is a 
nerve tonic and antidepressant. For mild depression, take 30 
drops with water 4 times a day.Infusion (to make, p. 291) is a 
tonic and is useful for urinary 
infections. Drink 3/4 cup (150 ml) 
daily as a general tonic.Damiana is a traditional aphrodisiac of the Maya 
people in Central America. It continues to be considered valuable as an aphrodisiac and general tonic, and its stimulant, tonic action also makes it  
a valuable remedy for those suffering from mild depression. Damiana has a strongly aromatic, slightly bitter taste. The leaves are used to flavor liqueurs and are taken in Mexico as a substitute for tea. Dried leavesFresh leaves
Tablets usually also 
contain other herbs. T ake as a relaxing tonic. US_144-145_Turnera_Ulmus.indd   144 26/02/16   4:00 pm145Ulm Us r UbraKey medicinal plants
Capsules (to make, p. 292)  
For bronchitis, take a 200 mg 
capsule 2 –3 times a day.Ulmus rubra (Ulmaceae)
Slippery Elm
Habitat & Cultivation
Slippery elm is a native of the U.S.  
and Canada, and is most commonly 
found growing in the Appalachian 
Mountains. The tree thrives on high 
ground and dry soil. The inner bark  
of the trunk and branches is collected 
in spring. Related Species
White elm ( U. americana ) is used in  
a similar way to slippery elm, and was 
taken for coughs by the Mohicans. In 
Europe, the dried bark of elm ( Ulmus 
spp.) was used as a demulcent, and 
was first mentioned by Dioscorides 
in the 1st century ce. Key Constituents
■ Mucilage
■ Starch
■ Tannins
Key Actions
■ Demulcent
■ Emollient
■ Nutritive
■ LaxativeResearch
■ Mucilage  There is limited  
research into slippery elm, but its 
action as an herb with large quantities 
of mucilage is well understood. When 
the herb comes into direct contact 
with inflamed surfaces such as the 
skin or the intestinal membranes,  
it soothes and coats the irritated 
tissue, protects it from injury, and 
draws out toxins or irritants. ■ Reflex action  When slippery  
elm is taken internally, it is thought 
likely that it causes a reflex 
stimulation of nerve endings in  
the stomach and intestines that  
leads to secretion of mucus by the 
membranes of the urinary tract. Traditional &  
Current Uses
■ Nourishing  T aken regularly, 
slippery elm is a nutritious and 
soothing food that acts as a prebiotic, 
supporting beneficial bacterial growth 
within the gut. It is excellent as a baby 
food and during convalescence. ■ Digestive disorders  Slippery elm 
is a particularly soothing herb and can 
bring instant relief to acidity, diarrhea, 
and gastroenteritis. It will also help 
alleviate conditions such as colic, 
inflammation of the gut, constipation, 
hemorrhoids, diverticulitis, and 
irritable bowel syndrome. ■ Urinary problems  This herb  
is a useful remedy for urinary 
problems such as chronic cystitis. ■ Respiratory conditions  
Slippery elm has been used to treat 
all manner of chest conditions and 
has a soothing effect on everything 
from coughs and bronchitis to pleurisy 
and tuberculosis.Slippery elm
A large tree growing 
to 59 ft (18 m) with  
a brown trunk and 
rough gray-white bark 
on the branches. ■ External uses Applied externally, 
the herb softens and protects the 
skin. It also works very well as a 
“drawing” poultice for boils  
and splinters.Slippery elm  produces red-brown fruit, 
each consisting of a single seed,  
in summer. Parts Used
Key Preparations  
& Their UsesInner bark of 10-year-old 
slippery elm trees is collected 
in spring and powdered. Self-help Uses
■ Acidity & indigestion , p. 307. ■ Acne & boils , p. 305. ■ Constipation in children , p. 318. ■ Hemorrhoids , p. 302.This marvellous herb is a gentle and effective remedy 
for irritated states of the mucous membranes of  
the chest, urinary tubules, stomach, and intestines. It was used in many different ways by Native 
Americans—as a poultice for wounds, boils, ulcers, 
and inflamed eyes, and internally for fevers, colds, and 
bowel complaints. Slippery elm has a strongly 
mucilaginous “slippery” taste and texture.Bark contains mucilage that 
soothes irritated tissues
Dried barkFresh bark
Infusion  Mix 1 heaped tsp with  
3 cups (750 ml) of warm water. Infuse for 5 minutes. For  
diarrhea, drink a whole dose  
1–2 times a day.Poultice  For wounds, add several 
drops of calendula tincture to  
1 tsp of powder. Mix into a paste 
and apply ( see p. 295). Tablets  T ake for diarrhea.Powder  For acid indigestion, take 1 tsp with water 2–3 times daily. US_144-145_Turnera_Ulmus.indd   145 26/02/16   4:00 pm
146Urtica dioicaKey medicinal plantsHigh levels of 
nutrients are concentrated  in the leavesUrtica dioica (Urticaceae)
NettleNettle
A perennial growing  to 5 ft (1.5 m), with lance-shaped leaves and green flowers  with yellow stamens. Nettle can be cooked as a vegetable and 
tastes like spinach. Habitat & Cultivation
Nettle grows in temperate regions 
worldwide. The shoots are picked  in spring for use as a tonic and a vegetable. Aerial parts are picked in summer when the plant is in flower. The root is harvested in autumn. Related Species
The annual nettle (U. urens) is used in similar ways to U. dioica. Roman nettle (U. pilulifera) was the species most 
used by the Romans for “urtication” (beating with nettles to encourage blood to the surface), which they  did to keep themselves warm. Key Constituents
Aerial parts:
■ Flavonoids (quercitin)
■ Amines (histamine, choline,  
 acetylcholine, serotonin)
■ Glucoquinone
■ Minerals (calcium, potassium,  
 silicic acid, iron)Root:
■ Plant sterols (stigmast-4-en-zone  
 and stigmasterol)
■ PhenolsKey Actions
■ Diuretic
■ Tonic
■ Astringent
■ Prevents hemorrhaging
■ Anti-allergenic
■ Reduces prostate  
 enlargement (root) 
■ Anti-inflammatory
Research
■ Root Clinical trials over the past  
20 years have supported the root’s use  
in treating an enlarged prostate and easing lower urinary tract symptoms, though several tested it in combination with saw palmetto (Serenoa repens,  p. 136) rather than on its own. ■ Antiarthritic Studies into nettle’s 
benefit in osteoarthritis have had mixed results, though a 2009 French trial found it reduced patients’ required daily intake of anti-inflammatories when combined  with Vitamin E, zinc, and fish oil. ■ Seeds Results of a 2009 Iranian 
laboratory study suggested that the seeds are antioxidant and protect liver function. Traditional &  
Current Uses
■ Cleansing Nettle’s key traditional 
use is as a cleansing, detoxifying herb. It has a diuretic action, possibly due to its flavonoids and high potassium content, and increases urine production and the elimination of waste products. It helps many skin conditions and arthritic problems. ■ Astringent Nettle slows or  
stops bleeding from wounds and nosebleeds, and is good for heavy menstrual bleeding.■ Allergies Nettle is antiallergenic. It treats hay fever, asthma, itchy skin conditions, and insect bites. The juice can be used as a treatment for  
nettle stings. ■ Enlarged prostate  
Following research, nettle root has now become a common treatment for symptoms linked to having an enlarged prostate.Parts Used
Key Preparations & Their UsesAerial parts are eaten as a tonic vegetable 
and used to make medicinal preparations. Dried aerial parts
Fresh aerial parts
Dried root
SeedsFresh root
Self-help Uses
■ Allergic rhinitis including  
 hay fever, p. 300. ■ Anemia due to heavy  
 menstrual bleeding, p. 301. ■ Bites & stings, p. 303. ■ Mild asthma, p. 301. ■ Diaper rash, p. 318. ■ Hives, p. 303. ■ Nosebleeds, p. 310. Decoction of root (see  
p. 291). For enlarged prostate, 
drink 3/4 cup (150 ml) daily. Soup with nettle leaves, 
carrots and onions is rich  
in iron. Drink regularly.Ointment of leaves 
(to make, p. 295). For 
eczema, rub liberally.Root has important diuretic properties that make it useful  for prostate problems.Known for its sting, nettle has long been appreciated 
for its medicinal uses. In the 1st century ce, the Greek physician Dioscorides listed a range of uses—the fresh chopped leaves as a plaster for septic wounds, the juice for nosebleeds, and the cooked leaves mixed with myrrh to stimulate menstruation. Today, nettle is used for hay fever, arthritis, anemia, and, surprisingly, even for some skin conditions. Seeds  are thought to  
act to protect the liver. Capsules of leaf, (to make, p. 292). For enlarged prostate take a 300 mg capsule 
2–4 times a day. For heavy periods, take a 100 mg capsule 3 times a day. Tincture of root (to make, p. 292) helps allergies and skin conditions. For hay fever, take 1 tsp diluted with 1/2 cup (100 ml) water twice a day.Infusion of leaves (to make, p. 291). Drink 
3⁄4 cup (200 ml) daily as a tonic. US_146-147_Urtica_Vaccinium.indd   146 17/03/16   4:00 pm147Vaccinium myrtillusKey medicinal plants
Tincture  (to make, p. 292). T ake 
1⁄2 tsp a day for poor circulation.Capsules  T ake up to 4 x 500 mg 
capsules a day to improve 
circulation within the eye.Vaccinium myrtillus  (Ericaceae)
Bilberry, Blueberry
Bilberry fruit first came to attention in the World War II 
(1939–45) when pilots found that their night vision 
improved on eating bilberry jam. Since then research has 
shown that bilberries help the eyes to adjust to the dark, 
and stimulate the part of the retina most involved in 
seeing clearly, especially in dim or dark conditions. There is also the suggestion that bilberry fruit helps  
to correct nearsightedness. Habitat & Cultivation
Bilberry thrives in moist undergrowth 
on moors, hillsides, and heathland, 
throughout temperate regions of  
the northern hemisphere—Asia, 
Europe, and North America. Widely 
cultivated around the world, bilberry 
is propagated from seed in autumn, 
or from cuttings. The leaves are 
collected in summer, the fruit  
when ripe in late summer or  
early autumn. Related Species
Other members of the Ericaceae, 
such as bearberry ( Arctostaphyllos 
uva-ursi , p. 170), cowberry ( V. vitis-
idaea ), and cranberry ( V. macrocarpon ,  
p. 280) are used principally as  
urinary antiseptics. Key Constituents
■ Tannins (approximately 7%)
■ Proanthocyanins
■ Flavonoids
■ Fruit acids
■ Phenolic acids
■ Pectin
■ Vitamin B2, C, and caroteneKey Actions
■ Circulatory tonic
■ Antioxidant
■ Anti-inflammatory
■ Astringent
■ Urinary antiseptic
Research
■ Circulation  Clinical trials from 
1964 onward have shown that 
bilberry fruits protect peripheral 
circulation and capillaries. Symptoms 
that have been shown to improve 
with bilberry extracts include fluid 
retention, pain, pins and needles 
(paresthesia), and cramps—all 
resulting from impaired peripheral 
blood flow. ■ Eyesight  Different trials have  
also shown improvement to eyesight 
in the nearsighted, in those with 
retinal damage due to diabetes, and  
to high blood pressure in patients 
taking bilberry extracts, beta-
carotene, and retinol. Other 
conditions such as period pain and 
recovery from hemorrhoid 
operations may improve with bilberry. Traditional &  
Current Uses
■ Digestive problems  Bilberry 
fruit has long been used as a mild 
laxative (because of its sugars),  
and to relieve diarrhea (due to  
the tannins). It is also moderately 
antibacterial and, since it tastes 
pleasant, is useful for treating 
diarrhea and indigestion in children. ■ Circulatory disorders  Many 
circulatory disorders will benefit from 
the fruit’s ability to improve capillary 
function and heal inflammation. These include intermittent Bilberry
A deciduous shrub, 
growing to 16 in  
(40 cm) tall, with white 
or pink flowers and 
purple-black berries. claudication, Raynaud’s disease, 
varicose veins, hemorrhoids, easy 
bruising, and all conditions impairing 
blood flow to the eyes, particularly 
diabetes and high blood pressure. ■ Antioxidant The fruit is used to 
protect against tissue damage (it may 
prevent cataract formation) and to 
promote tissue healing, for example  
in the gastrointestinal tract or in 
rheumatoid or osteoarthritis.Bilberry fruit can be used as a natural 
antioxidant supplement.Parts Used
Key Preparations  
& Their Uses
■ Antiseptic  The leaves have a 
marked antiseptic effect within the 
bladder and urinary tubules, and can 
be used to treat urinary infections 
such as cystitis. ■ Antidiabetic  The leaves and  
fruit have antidiabetic activity,  
helping especially in pre-diabetic 
states. There is growing evidence  
that the fruit can help to promote 
weight loss. QCaution  If taking anticoagulants or diagnosed with a bleeding disorder, take 
medicinal doses on professional advice only.Leaves  make a useful urinary antiseptic 
and astringent for urinary tract problems 
such as cystitis and irritable bladder. Berries  have a strong healing 
effect on capillaries, especially 
on the micro-circulation within 
the eye. Fresh leavesFresh 
berries
Dried berries
Tablets,  like capsules, are convenient for long-term use.Decoction  (to make, p. 291) is pleasant-tasting and useful for short-term 
treatment of diarrhea in children. US_146-147_Urtica_Vaccinium.indd   147 26/02/16   4:00 pm
148Valeriana officinalisKey medicinal plants
Valepotriates in 
the rhizome and root induce sleepValeriana officinalis (Valerianaceae)
ValerianValerian
Erect perennial growing to 4 ft  
(1.2 m), with pinnate divided leaves and pink flowers. Valerian helps reduce stress. Its name is 
thought to be derived from the Latin valere, “to be well.”
Habitat & Cultivation
Native to Europe and northern  
Asia, valerian grows wild in  
damp conditions. It is cultivated  in central and eastern Europe. The plant is grown from seed in spring, and the root and rhizome  of 2-year-old plants are unearthed  in autumn. Related Species
V. capensis is given in South Africa  for hysteria and epilepsy; V. hardwickii, found in China and Indonesia, is taken as an antispasmodic; V. ulginosa was used for cramps and menopausal symptoms by the Menominee people in North America; and V. wallichi is used in the Himalayas in almost exactly the same way as valerian. Key Constituents
■ Volatile oil (up to 1.4%),  
 including bornyl acetate,   beta-caryphyllene
■ Iridoids (valepotriates)— 
 valtrate, isovaltrate
■ AlkaloidsKey Actions
■ Sedative
■ Relaxant
■ Relieves muscle spasms
■ Relieves anxiety
■ Lowers blood pressure
Research
■ Therapeutic properties 
Extensive research in Germany and Switzerland has endorsed the use of valerian to aid sleep, improve sleep quality, and lower blood pressure. A German trial carried out in 2002 that tested valerian and oxazepam  
(a conventional sleep treatment) found both to be effective—83% of those taking valerian rated the treatment as very good compared to 73% of those taking oxazepam. Traditional &  
Current Uses
■ Historical uses Known as “all-
heal” in the Middle Ages, valerian  
was credited with many virtues, in 
particular with healing epilepsy. In 1592, Fabius Calumna published  
a detailed work on herbal medicine  
in which he claimed to have cured  his epilepsy with the herb. ■ Stress-related disorders 
Valerian reduces mental over-  
activity and nervous excitability, helping people who find it hard  
to “switch off.” It is beneficial for almost any stress-related condition, and, in general, has a calming, rather than directly sedative, effect on  the mind. ■ Anxiety & insomnia Many 
symptoms of anxiety, including tremors, panic, palpitations, and sweating, can be relieved with valerian. It is a useful remedy for insomnia, whether caused by anxiety or overexcitement. ■ Effective relaxant Valerian relaxes 
overcontracted muscles, and is helpful for shoulder and neck tension, asthma, colic, irritable bowel syndrome, period pain, and muscle spasms. ■ High blood pressure Valerian  
is used with other herbs in remedies Parts Used
Key Preparations & Their UsesRoot and rhizome are harvested in autumn when  
they contain the highest level of active ingredients. Fresh root  
and rhizomeDried root  
and rhizome
for high blood pressure caused  
by stress and anxiety. Self-help Uses
■ Chronic anxiety, p. 308. ■ Insomnia, p. 309. ■ Nervous exhaustion, p. 309. ■ Premenstrual syndrome, p. 315. ■ Sleeplessness due to  
 backache, p. 313.Tincture (to make, p. 292). For anxiety, take 20 drops in 
hot water up to 5 times a day.Tablets often also contain other 
herbs. T ake for stress or anxiety. Powder  can be taken as 
capsules (to make, p. 292). For insomnia, take 1 –2 doses of 500 mg at night.Valerian has been used as a sedative and relaxant at  
least since Roman times. It was known to Dioscorides  
in the 1st century ce, who named it phu, the sound of  the word reflecting its unpleasant smell. Valerian helps relieve stress and has become an increasingly popular remedy in recent decades. It is a safe, nonaddictive relaxant that reduces nervous tension and anxiety and promotes restful sleep. QCautions Can cause drowsiness. Do not take valerian if already taking  
sleep-inducing drugs. Decoction (to make, p. 291). T ake 1–5 tbsp as a sedative at night. US_148-149_Valeriana_Verbena.indd   148 07/04/16   4:37 pm149Verbena officinalisKey medicinal plants
Infusion  (to make, p. 291) helps stimulate 
digestion and improves effective 
absorption of food. Drink 3/4 cup (150 ml) 
regularly, particularly after heavy meals. Powder  can be used as a toothpaste. Rub on the teeth regularly to clean  
and protect them.Tincture  (to make, p. 292) is a relaxing, 
calming tonic. For stress and anxiety, 
take 1⁄2 tsp diluted in a glass of water  
3 times a day.Vervain has 
slender, almost 
“wandlike,” 
flowering stemsVerbena officinalis (Verbenaceae)
Vervain, Ma Bian Cao (Chinese)
Habitat & Cultivation
Vervain grows wild throughout  
much of Europe and North Africa  
as well as in China and Japan. It is 
propagated from seed in spring or 
autumn and thrives in well-drained 
soil in a sunny position. The aerial 
parts are harvested in summer  
when the plant is in flower. Related Species
Blue vervain ( V. hastata ), which  
is native to North America, is  
used medicinally in the same  
way as vervain. Key Constituents
■ Bitter iridoids  
 (verbenin, verbenalin)
■ Volatile oil
■ Alkaloids
■ Triterpenes (beta-sitosterol)
■ Flavonoids
Key Actions 
■ Nervine
■ Tonic
■ Mild bitter
■ Mild antidepressantResearch
■ Hormonal effects  Early 
indications from research into vervain 
are that it has both estrogenic  
and progestogenic activity. It also 
stimulates the muscles of the womb, 
and production of breast milk. ■ Lack of research For an herb 
with such long traditional use, 
surprisingly little research into vervain 
has occurred to date. Laboratory 
studies indicate that vervain has 
significant anti-inflammatory activity. It may also have antiviral and liver-
protective properties. Verbenalin, an 
active compound within vervain, is 
strongly bitter, may cause vomiting at 
high doses, and stimulates contraction 
of the womb. Traditional & 
Current Uses
■ Digestive tonic  Vervain improves 
the function of the digestive system 
and absorption of food. ■ Nervous system  Vervain is  
prized as a restorative for the nervous 
system and is especially helpful for 
nervous tension. It is thought to have  
a mild antidepressant action, and is 
used specifically to treat anxiety and 
the nervous exhaustion that follows 
long-term stress. ■ Convalescence  By aiding 
digestion and restoring the nervous 
system, vervain is an ideal tonic for 
people recovering from chronic illness. ■ Headaches & migraines  
Vervain alleviates headaches, and in 
Chinese herbal medicine it is used  
for migraines connected with the 
menstrual cycle. ■ Other uses Among its other 
medicinal uses, vervain is given  Vervain
A slender perennial 
growing to 3 ft (1 m), 
with stiff, thin stems 
and spikes of small 
lilac flowers. Vervain was carried in the Middle Ages  
to bring good luck. Parts Used
Key Preparations & Their UsesAerial parts have a tonic 
effect on the nervous system 
and digestion, and have been 
used medicinally for thousands 
of years in Europe and China. Dried aerial parts
Fresh aerial partsVervain has long been credited with magical properties  
and was used in ceremonies by the Druids of ancient 
Britain and Gaul. It is a traditional herbal medicine in both 
China and Europe. Dioscorides in the 1st century ce 
called vervain the “sacred herb,” and for many centuries  
it was taken as a cure-all. It has tonic, restorative properties, 
and is used to relieve stress and anxiety and to improve 
digestive function. QCautions  Do not exceed the stated dose. Vervain can cause vomiting if taken  
in excess. Do not take during pregnancy. for jaundice, gallstones, asthma, 
insomnia, premenstrual syndrome,  
flu, and fevers. Self-help Uses
■ Nervous exhaustion , p. 309. ■ Premenstrual syndrome , p. 315. US_148-149_Valeriana_Verbena.indd   149 17/03/16   4:01 pm
150Viburnum opulusKey medicinal plantsViburnum opulus (Caprifoliaceae)
Cramp Bark, Guelder RoseCramp bark
A deciduous shrub  or tree growing to  13 ft (4 m), with lobed leaves, white flowers, and red oval fruit. Cramp bark has distinctive bright red 
berries in autumn. Habitat & Cultivation
Cramp bark grows in woodlands, 
hedges, and thickets in Europe  
and eastern North America. It  
is propagated from seed sown  
in autumn. Bark from the  
branches is collected in spring  
and summer, when the plant is  
in flower. Related Species
Black haw (V. prunifolium, p. 281)  
is often used interchangeably  
with cramp bark, but it is thought  
to have a more specific action  
on the uterus. Key Constituents
■ Hydroquinones (arbutin)
■ Coumarins (scopoletin)
■ Tannins (3%)
■ Proanthocyanidins
■ Polysaccharides
Key Actions
■ Antispasmodic
■ Sedative
■ Astringent
■ RelaxantResearch
■ Active constituents To date, 
cramp bark has been poorly researched, and there is also some confusion over which active constituents it contains and which occur in the closely related black  haw (V. prunifolium). Traditional  
& Current Uses
■ Native American remedy  
Cramp bark has a history of use  
in Native American herbalism. The Meskwaki people took  
cramp bark for cramps and pains throughout the body, while the Penobscot used it to treat swollen glands and mumps. ■ Muscle relaxant Cramp bark  
is effective at relieving any tense muscle, whether smooth muscle in the intestines, airways, or uterus,  or striated muscle (attached to  the skeleton) in the limbs or back. It may be taken internally, or applied topically to relieve muscle tension. The herb also treats symptoms arising from excess muscle tension, including breathing difficulties in asthma, and menstrual pain caused by excessive contraction of the uterus. For night cramps and back pain, lobelia (Lobelia inflata, p. 110)  is often mixed with cramp bark. The herb also relieves constipation, colic, and irritable bowel syndrome, as well as the physical symptoms of nervous tension. ■ Arthritis In some cases of 
arthritis, where joint weakness  
and pain have caused muscles to contract until they are almost rigid, cramp bark can bring remarkable relief. As the muscles relax, blood flow to the area improves, waste products such as lactic acid are removed, and normal function  
can return. ■ Other uses Cramp bark is 
commonly used in treatments  
for high blood pressure and other circulatory conditions.Parts Used
Key Preparations & Their UsesBark is peeled off the tree 
in strips during spring and summer. Care must be taken to leave enough bark for the tree to stay alive. Dried bark
Tincture (to make, p. 292) is  
used for long-term treatment  
of muscular tension. For irritable 
bowel syndrome, take 1⁄2 tsp 
diluted with hot water twice a day.Decoction (to make, p. 291). For period pain, take 1/3 cup 
(75 ml) every 3 hours. Self-help Uses
■ Back pain, p. 313. ■ Breathing difficulties, p. 301. ■ Cramps & muscle spasms, p. 312. ■ Period pain, p. 315. ■ Poor circulation to the  
 hands & feet, p. 302. ■ Spastic constipation, p. 307. ■ Stomach spasm, p. 305.Lotion (to make, p. 296) relieves 
aching muscles. Rub into tense  neck and shoulders.Fresh barkNative to both North America and Europe, cramp  
bark was recognized as recently as 1960 in the US  
National Formulary as a sedative remedy for nervous conditions and as an antispasmodic in the treatment  
of asthma. As its name implies, the herb’s primary medicinal use is to relieve cramps and other conditions, such as colic or painful menstruation, caused by overcontraction of muscles. US_150-151_Viburnum_Vitex.indd   150 07/04/16   4:37 pm151Vitex agnus-castusKey medicinal plants
Tablets T ake for premenstrual syndrome.Tiny yellow-red 
berries contain 
hormonal 
substancesVitex agnus-castus  (Verbenaceae)
Chaste Tree, Agnus Castus
Chaste tree was well known in ancient times and  
featured in Homer’s 6th-century bce epic, the Iliad, as  
a symbol of chastity capable of warding off evil. As the  
name “chaste tree” implies, it was thought to reduce  
sexual desire, and traditionally it was chewed by monks  
to reduce unwanted libido. Research has confirmed that 
chaste tree has a hormonal action, and today it is used  
for menstrual problems and infertility. Habitat & Cultivation
Chaste tree is native to the 
Mediterranean region and western 
Asia. It is cultivated in subtropical 
areas around the world, and has 
become naturalized in many regions. It is grown from seed in spring  
or autumn. The ripe berries are 
collected in autumn. Related Species
As a member of the Verbenaceae 
genus, chaste tree is a distant  
relative of vervain ( Verbena officinalis , 
p. 149) and lemon verbena ( Lippia 
citriodora , p. 228). Key Constituents
■ Volatile oil (cineol) 
■ Flavonoids (casticin)
■ Iridoids (aucubin, agnoside,  
 eurostoside)
■ Diterpenes
Key Actions
■ Regulates hormones
■ Progesterogenic
■ Increases breast-milk production
■ Aids sleepResearch
■ Hormonal properties  The 
berries are thought to induce subtle 
hormonal effects within the brain, 
leading to increased levels of the 
neurotransmitters dopamine and 
melatonin. These changes are 
thought to promote better hormonal 
regulation of the menstrual cycle, 
notably through raised progesterone 
levels. In some people, the raised 
melatonin levels may aid sleep quality. The diterpenes are thought to be 
chiefly responsible for these effects. ■ Gynecological problems 
Clinical research by and large 
supports the use of chaste tree in 
many female hormonal problems, 
including premenstrual syndrome 
(PMS), irregular menstruation, 
breast tenderness, and infertility. A 2001 clinical trial tested chaste 
berry against placebo in 178 women 
with PMS. After 3 months, those 
taking chaste tree had a 50% 
reduction in symptoms compared  
to placebo. ■ Sleep aid  Since researchers 
found that chaste berry increases 
melatonin levels, chaste berry has 
been thought of as a possible sleep 
aid. Some small studies indicate that 
chaste berry might help people with 
insomnia due to unhealthy melatonin 
levels, such as shift workers or those 
who are jet lagged. Traditional  
& Current Uses
■ Menstrual problems  Chaste 
tree is probably the most used herb 
in Western herbal medicine for 
regulating the menstrual cycle. With 
its progestogenic action, chaste tree Chaste tree
A deciduous aromatic 
tree growing to 23 ft 
(7 m), with palm-
shaped leaves and  
small lilac flowers. is often helpful in relieving 
premenstrual symptoms, including 
irritability and lowered mood, 
headache, acne, and breast 
tenderness. Chaste tree also 
promotes greater menstrual 
regularity, and this use extends to 
more significant hormonal problems 
including polycystic ovary syndrome, 
fibroids, and endometriosis. ■ Irregular periods  The herb 
helps to regulate irregular periods, 
tending to shorten a long cycle and 
lengthen a short one. ■ Infertility  Chaste tree can be  
of help to some women trying to 
conceive if infertility is due to low 
progesterone levels. Chaste tree  has small, fragrant, lilac flowers in 
summer that grow in whorls on long spikes.Parts Used
Key Preparations  
& Their UsesBerries , harvested in  
autumn, are used to treat 
female fertility problems. Fresh berries
■ Difficulty in breastfeeding  The 
berries are taken to increase breast-
milk production. ■ Acne  Though rarely used on its 
own, chaste tree can be extremely 
helpful in treating acne in both men 
and women. Used in combination 
with herbs such as echinacea 
(Echinacea  spp., p. 92), it will often 
reduce the frequency and intensity  
of acne blemishes where hormonal 
imbalance is a major factor. Self-help Uses
■ Aiding conception , p. 316. ■ Decreased estrogen & 
progesterone levels , p. 316. ■ Irregular cycle , p. 315.Dried berries
 QCaution Excess can cause formication (a sensation of ants 
crawling on the skin). Concurrent use with the contraceptive pill 
or fertility treatment is not advisable. Avoid in pregnancy. In rare 
cases may cause gastrointestinal upset, headache, or dizziness. Tincture  (to make, p. 292). For an irregular cycle, take 40 drops with water 
daily for 3 months. US_150-151_Viburnum_Vitex.indd   151 26/02/16   4:00 pm
152Withania somniferaKey medicinal plantsWithania somnifera (Solanaceae)
AshwagandhaAshwagandha
A stout shrub growing to 5 ft (1.5 m), with oval leaves and greenish or yellow flowers. Ashwagandha has powerful medicinal 
properties proven by research. Habitat & Cultivation
Ashwagandha is found in India,  
the Mediterranean, and the Middle East. It is propagated from seed  or cuttings in spring. The leaves are harvested in spring, and the fruit  and root in autumn. Key Constituents
■ Alkaloids
■ Steroidal lactones (withanolides)
■ Iron
Key Actions
■ Adaptogenic
■ Tonic
■ Mild sedative
Research
■ Chronic stress Clinical research 
has been wide-ranging and examined many aspects of ashwagandha’s potential medicinal uses, many linked to the withanolides, compounds similar to the body’s own steroid hormones. A 2012 Indian clinical trial noted that those taking ashwagandha had lower stress  
levels and an increased sense of well-being, as well as lower cortisol and blood pressure levels. ■ Anxiety and tension  
Ashwagandha has been proven to  
reduce anxiety and tension in at least 6 clinical trials. In a 2009 Canadian trial, ashwagandha, paired with dietary advice and a multivitamin supplement, was found more effective in decreasing anxiety than psychotherapy and a placebo. Those taking ashwagandha also reported improved concentration and less fatigue. ■ Male fertility Two clinical trials 
testing ashwagandha’s role as a male sexual tonic indicate that the herb markedly improves semen quality. Another clinical trial failed to find any benefit in aiding erectile dysfunction. ■ Other actions Ashwagandha has 
also been researched for its use as a tonic suitable for children, to improve muscle strength and mental function in the elderly, for arthritis, and to enhance immune function. Ashwagandha is thought to have anticancer activity. Traditional  
& Current Uses
■ Ayurvedic tonic Ashwagandha 
has always been valued in Ayurveda 
for its tonic, strengthening, and relaxing properties. Robert Svoboda in Ayurveda: Life, Health, and Longevity states that it “clarifies the mind, calms and strengthens the nerves, and promotes sound restful sleep.”
■ Restorative Today, the herb is still 
prized as a tonic, but valued also for its unusual combination of actions. As a tonic, it strengthens and supports physical and mental performance, yet at the same time it relieves anxiety Parts Used
Key Preparations & Their UsesLeaves contain the most 
withanolides, constituents that inhibit cancer cell growth. Root is powdered or made into decoctions and taken as a strengthening  and calming tonic. Fresh rootDried leaves
Fresh plant
Dried root
Decoction of the root (to make, p. 291). For stress, decoct 5 g with 1/3 cup (75 ml) 
water and take over 2 days.Powder  made from the leaves. For anemia, take 1⁄2 tsp in a little 
water once a day.Berries are chewed in India to help in convalescence. Fresh berries Dried berriesAshwagandha has been called “Indian ginseng” because it is 
used in Ayurveda in much the same way that ginseng is used in Chinese medicine: to improve vitality and to aid recovery after chronic illness. Today, ashwagandha seems to be an herb designed to deal with the busy nature of modern life. It invigorates when fatigued, eases the impact of stress and anxiety, and aids sleep—all traditional uses largely supported by clinical research. and, as its botanical name suggests, 
encourages better sleep quality. It is an excellent herb for convalescence. ■ Inflammatory conditions 
Ashwagandha can be a useful addition to treatment for chronic inflammatory diseases such as rheumatoid arthritis and psoriasis. ■ Long-term stress By reducing 
overactivity and encouraging rest and relaxation, ashwagandha is  
useful in countering the debility that accompanies long-term stress. ■ Anemia Aswagandha’s high iron 
content makes it useful in anemia. Self-help Uses
■ Long-term stress &   
 convalescence, pp. 308 & 319. ■ Male fertility, p. 316.Capsules of powdered root (to make, p. 292). For nervous exhaustion,  
take 1 –2 g a day with water. US_152-153_Withania_Zanthoxylum.indd   152 26/02/16   4:00 pm153Zanthoxylum americanumKey medicinal plants
Decoction  For poor circulation, decoct  
3 tsp ginger and 3 tsp prickly ash berries 
with 3 cups (750 ml) water ( see p. 291). T ake 3/4 cup (150 ml) twice a day. Tablets  T ake tablets, which often contain 
other herbs, for arthritis and rheumatism. Lotion  For poor circulation in the legs, make 
a decoction of bark (p. 291) and apply.Tincture  of bark (to make, p. 292). For arthritis, take 20 drops with 
water 3 times a day.Zanthoxylum americanum  (Rutaceae)
Prickly ash, Toothache Tree
Indigenous to North America, prickly ash is  
a warming, stimulating herb for circulation. It was  
held in high regard by Native North Americans for its  
medicinal properties, and both the bark and berries  
were chewed to alleviate rheumatism and toothache. Today, prickly ash is mainly given for arthritic  
and rheumatic conditions, but it is also helpful for  
certain digestive problems and for leg ulcers. Habitat & Cultivation
Prickly ash is native to southern 
Canada and northern, central, and 
western parts of the U.S., preferring 
moist, shady sites such as woodlands. It is propagated from seed in 
autumn. The bark is harvested in 
spring and the berries are collected 
in summer. Related Species
Southern prickly ash ( Z. clava-herculis ) 
grows in the central and southern 
U.S., where it is used interchangeably  
with prickly ash. Chuan jiao   
(Z. bungeanum ) is given in Chinese 
herbal medicine for “cold” patterns 
of illness causing abdominal pain. Z. capense  is taken for colic in  
South Africa. Z. zanthoxyloides  is a 
traditional West African herb for 
rheumatic conditions. Key Constituents
■ Isoquinoline alkaloids
■ Furanocoumarins
■ Lignans
■ Volatile oil
■ TanninsKey Actions
■ Circulatory stimulant
■ Increases sweating
■ Antirheumatic
■ Antifungal
Research
■ Antifungal  Research into prickly 
ash is limited, though a 2005 study 
found extracts from prickly ash fruit 
and leaf demonstrated antifungal 
activity. Traditional  
& Current Uses
■ North American herb  Prickly 
ash was a Native American remedy 
for toothache and rheumatism. It was 
used in the U.S. during the 19th 
century as a circulatory stimulant and 
to treat arthritis. ■ Arthritic conditions  Western 
herbalists regard northern prickly  
ash as a prime remedy for rheumatic 
and arthritic problems. It stimulates 
blood flow to painful and stiff joints, 
promoting the supply of oxygen and 
nutrients to the area and removing 
waste products. ■ Circulation  The herb improves 
circulation in intermittent claudication 
and Raynaud’s disease, conditions 
where the arteries of the limbs have 
narrowed, preventing sufficient blood 
reaching the hand or leg muscles. ■ Other uses  Prickly ash relieves gas 
and diarrhea and tones the digestive 
tract. It is applied topically to treat leg 
ulcers and chronic pelvic 
inflammatory disease. Self-help Uses
■ Back pain , p. 313. ■ Poor circulation , p. 302Prickly ash
A deciduous shrub 
growing to 10 ft (3 m), 
with thorny gray  
branches and  
compound leaves. Prickly ash  is antirheumatic and improves 
circulation.Parts Used
Key Preparations & Their UsesBark is considered to 
have a stronger effect 
than the berries. It is 
used in preparations  
to stimulate blood flow. Berries are made  
into remedies for  
poor circulation. Dried chopped barkFresh bark
Dried berriesFresh plant
 QCautions  Avoid in pregnancy and while breastfeeding.Berries and bark  
were chewed  
for toothache
US_152-153_Withania_Zanthoxylum.indd   153 26/02/16   4:00 pm
154Zea maysKey medicinal plants Y ellow, inner 
cornsilk is  used medicinallyZea mays (Poaceae)
Corn, Maize, Cornsilk, Yu Mi Shu (Chinese)Corn
An annual grass reaching 10 ft (3 m), with plumelike  male flowers. Female flowers produce cobs. Corn’s Latin name reflects its value— 
zea means “cause of life” and mays means 
“our mother.”
Habitat & Cultivation
Cultivated almost universally as a 
food crop, corn is native to the Andes and Central America, possibly originating in Peru. It is propagated from seed in spring. The cornsilk  is harvested with the ripe cob in summer, then separated and dried.
Encyclopedia_Of_Herbal_Medicine.txt
Summarize the following text section accurately and concisely. Maintain specific details and numerical information, and use anti-repetition mechanisms:

        Recent research has confirmed 
traditional herbal knowledge, proving that the herb has  
a remarkable ability to protect the liver from damage 
resulting from alcoholic and other types of poisoning. Today, milk thistle is widely used in the West for the 
treatment of a range of liver conditions. Tablets  are prescribed for long-term treatment of liver disorders. Spiny, thistle- 
like leaves are 
gray-green
Seeds contain silymarin, 
which protects the liver. They are the main part 
used in remedies. Flower heads  are eaten as a tonic 
food and can be used in remedies. Fresh flower 
head
Dried flower 
head
Seeds
US_136-137_Serenoa_Silybum. indd   137 26/02/16   4:00 pm
138Symphytum officinaleKey Medicinal plants
Aerial parts are rich 
in anti-inflammatory and astringent substances. Root is harvested in autumn when the allantoin levels are highest. Infused oil of leaves 
(to make, p. 294). Apply to sprains. Chopping leaves  For boils, apply as a poultice (see p. 295). Ointment of leaves  (to make, p.
To protect the liver from damage resulting from poisoning.
What is the primary use of milk thistle?
As a wound-healing agent and for the treatment of broken bones.
What is the traditional use of comfrey?
To improve the eyesight and treat various skin conditions.
What is the primary use of bilberry?
To improve the eyesight and treat various skin conditions.
What is the primary use of bilberry?
To improve vitality, reduce stress, and promote relaxation.
What is the primary use of ashwagandha?
To relieve arthritic and rheumatic conditions.
What is the primary use of prickly ash?