Barbiturate Barbiturates are drugs that act as central nervous system depressants, and can therefore produce a wide spectrum of effects, from mild sedation to total anesthesia. They are also effective as anxiolytics,<unk> s, and anticonvulsalgesic effects; however, these effects are somewhat weak, preventing barbiturates from being used in surgery in the absence of other analgesics. They have dependence liability, both physical and psychological. Barbiturates have now largely been replaced by benzodiazepines in routine medical practice – such as in the treatment of anxiety and insomnia – mainly because benzodiazepines are significantly less dangerous in overdose. However, barbiturates are still used in general anesthesia, for epilepsy, and for assisted suicide. Barbiturates are derivatives of barbituric acid. The principal mechanism of action of barbiturates is believed to be positive allosteric modulation of GABAA receptors. Examples include amobarbital, pentobarbital, phenobarbital, secobarbital, and sodium thiopental. Quinazolinones Quinazolinones are also a class of drugs which function as<unk> /sedatives that contain a 4-quinazolinone core. Their use has also been proposed in the treatment of cancer. Examples of quinazolinones include cloroqualone, diproqualone, etaqualone (Aolan, Athinazone, Ethinazone), mebroqualone, Afloqualone (Arofuto), mecloqualone (Nubarene, Casfen), and methaqualone (Quaalude). Benzodiazepines Benzodiazepines can be useful for short-term treatment of insomnia. Their use beyond 2 to 4 weeks is not recommended due to the risk of dependence. It is preferred that benzodiazepines be taken intermittently—and at the lowest effective dose. They improve sleep-related problems by shortening the time spent in bed before falling asleep, prolonging the sleep time, and, in general, reducing wakefulness. Like alcohol, benzodiazepines are commonly used to treat insomnia in the short-term (both prescribed and self-medicated), but worsen sleep in the long-term. While benzodiazepines can put people to sleep (i.e., inhibit NREM stage 1 and 2 sleep), while asleep, the drugs disrupt sleep architecture by decreasing sleep time, delaying time to REM sleep, and decreasing deep slow-wave sleep (the most restorative part of sleep for both energy and mood). Other drawbacks of<unk> s, including benzodiazepines, are possible tolerance to their effects, rebound insomnia, and reduced slow-wave sleep and a withdrawal period typified by rebound insomnia and a prolonged period of anxiety and agitation. The list of benzodiazepines approved for the treatment of insomnia is fairly similar among most countries, but which benzodiazepines are officially designated as first-line<unk> s prescribed for the treatment of insomnia can vary distinctly between countries. Longer-acting benzodiazepines such as nitrazepam and diazepam have residual effects that may persist into the next day and are, in general, not recommended. It is not clear as to whether the new nonbenzodiazepine<unk> s (Z-drugs) are better than the short-acting benzodiazepines. The efficacy of these two groups of medications is similar. According to the US Agency for Healthcare Research and Quality, indirect comparison indicates that side-effects from benzodiazepines may be about twice as frequent as from nonbenzodiazepines. Some experts suggest using nonbenzodiazepines preferentially as a first-line long-term treatment of insomnia. However, the UK National Institute for Health and Clinical Excellence (NICE) did not find any convincing evidence in favor of Z-drugs. A NICE review pointed out that short-acting Z-drugs were inappropriately compared in clinical trials with long-acting benzodiazepines. There have been no trials comparing short-acting Z-drugs with appropriate doses of short-acting benzodiazepines. Based on this, NICE recommended choosing the<unk>  based on cost and the patient's preference. Older adults should not use benzodiazepines to treat insomnia—unless other treatments have failed to be effective. When benzodiazepines are used, patients, their caretakers, and their physician should discuss the increased risk of harms, including evidence which shows twice the incidence of traffic collisions among driving patients, as well as falls and hip fracture for all older patients. Their mechanism of action is primarily at GABAA receptors. Nonbenzodiazepines Nonbenzodiazepines are a class of psychoactive drugs that are very "benzodiazepine-like" in nature. Nonbenzodiazepine pharmacodynamics are almost entirely the same as benzodiazepine drugs, and therefore entail similar benefits, side-effects and risks. Nonbenzodiazepines, however, have dissimilar or entirely different chemical structures, and therefore are unrelated to benzodiazepines on a molecular level. Examples include zopiclone (Imovane, Zimovane), eszopiclone (Lunesta), zaleplon (Sonata), and zolpidem (Ambien, Stilnox, Stilnoct). Research on nonbenzodiazepines is new and conflicting. A review by a team of researchers suggests the use of these drugs for people that have trouble falling asleep (but not staying asleep), as next-day impairments were minimal. The team noted that the safety of these drugs had been established, but called for more research into their long-term effectiveness in treating insomnia. Other evidence suggests that tolerance to nonbenzodiazepines may be slower to develop than with benzodiazepines. A different team was more skeptical, finding little benefit over benzodiazepines. Others Melatonin Melatonin, the hormone produced in the pineal gland in the brain and secreted in dim light and darkness, among its other functions, promotes sleep in diurnal mammals. Antihistamines In common use, the term antihistamine refers only to compounds that inhibit action at the H1 receptor (and not H2, etc.). Clinically, H1 antagonists are used to treat certain allergies. Sedation is a common side-effect, and some H1 antagonists, such as diphenhydramine (Benadryl) and doxylamine, are also used to treat insomnia. Second-generation antihistamines cross the blood–brain barrier to a much lower degree than the first ones. This results in their primarily affecting peripheral histamine receptors, and therefore having a much lower sedative effect. High doses can still induce the central nervous system effect of drowsiness. Antidepressants Some antidepressants have sedating effects. Examples include: ; Serotonin antagonists and reuptake inhibitors * Trazodone ; Tricyclic antidepressants * Amitriptyline * Doxepin * Trimipramine ; Tetracyclic antidepressants * Mianserin * Mirtazapine Antipsychotics Examples of antipsychotics with sedation as a side effect that are occasionally used for insomnia: ; First-generation * Chlorpromazine ; Second-generation * Clozapine * Olanzapine * Quetiapine * Risperidone * Zotepine Miscellaneous drugs ;Alpha-adrenergic agonist * Clonidine * Guanfacine ;Cannabinoids * Cannabidiol * Tetrahydrocannabinol ;Orexin receptor antagonist * Suvorexant * Lemborexant ;Gabapentinoids * Gabapentin * Pregabalin * Phenibut
Hypnotic
Depressive
Sedative
Eugeroic
Psychotomimetic
Catagmatic
Anesthetic
Grief