<unk>  may cause upset stomach, diarrhea, dizziness, unsteadiness, drowsiness, mouth sores, headache, and vomiting. It increases sensitivity to sunlight, and may affect the quality of sleep and rarely causes sleep disorders. It has also been linked to cases of lupus. Prolonged use of<unk>  can lead to blue-gray staining of skin, fingernails, and scar tissue. This staining is not permanent, but can take a very long time for the skin color to return to normal; however, a muddy brown skin color in sun-exposed areas is usually permanent. Permanent blue discoloration of gums or teeth discoloration may also occur. Rare but serious side effects include fever, yellowing of the eyes or skin, stomach pain, sore throat, vision changes, and mental changes, including depersonalization. Occasionally,<unk>  therapy may result in autoimmune disorders such as drug-related lupus and autoimmune hepatitis, which usually occurs in men who also developed<unk> -induced lupus; however, women are more likely to develop<unk> -induced lupus. Significant or complete recovery occurs in most people who develop<unk> -induced autoimmune problems within a period of a few weeks to a year of cessation of<unk>  therapy. Autoimmune problems emerge during chronic therapy, but can sometimes occur after only short courses of a couple of weeks of therapy. Drug reaction with eosinophilia and systemic symptoms syndrome can occur during the first few weeks of therapy with<unk> .<unk> , but not other tetracyclines, can cause vestibular disturbances with dizziness, ataxia, vertigo, and tinnitus. These effects are thought to be related to<unk> 's greater penetration into the central nervous system. Vestibular side effects are much more common in women than in men, occurring in 50 to 70% of women receiving<unk> . As a result of the frequency of this bothersome side effect,<unk>  is rarely used in female patients. Symptoms of an allergic reaction include rash, itching, swelling, severe dizziness, and trouble breathing.<unk>  has also been reported to very rarely cause idiopathic intracranial hypertension (pseudotumor cerebri), a side effect also more common in female patients, potentially leading to permanent vision damage if not recognized early and treated. Contrary to most other tetracycline antibiotics (doxycycline excluded),<unk>  may be used in those with kidney disease, but may aggravate systemic lupus erythematosus. It may also trigger or unmask autoimmune hepatitis.<unk>  can cause the rare condition of secondary intracranial hypertension, which has initial symptoms of headache, visual disturbances, dizziness, vomiting, and confusion. Brain swelling and rheumatoid arthritis are rare side effects of<unk>  in some people.<unk> , like most tetracyclines, becomes dangerous past its expiration date. While most prescription drugs lose potency after their expiration dates, tetracyclines are known to become toxic over time. Expired tetracyclines can cause serious damage to the kidney due to the formation of a degradation product, anhydro-4-epitetracycline.<unk> 's absorption is impaired if taken at the same time of day as calcium or iron supplements. Unlike some of the other tetracycline group antibiotics, it can be taken with calcium-rich foods such as milk, although this does reduce the absorption slightly.<unk> , like other tetracyclines, is associated with esophageal irritation and ulceration if insufficient fluids are taken with the drug before sleep. A 2007 study suggested that<unk>  harms amyotrophic lateral sclerosis patients. Patients on<unk>  declined more rapidly than those on placebo. The mechanism of this side effect is unknown, although a hypothesis is that the drug exacerbated an autoimmune component of the primary disease. The effect does not seem to be dose-dependent because the patients on high doses did not do worse than those on the low doses. The use of<unk>  in acne vulgaris has been associated with skin and gut dysbiosis (see antibiotic misuse).
Minocycline
Tetracycline
Extended-spectrum penicillin
Sarecycline
Cephalosporin
Oxytetracycline
Teicoplanin
Doxycycline