Chloral hydrate was discovered in 1832, and was used as a sedative in late 19th century. Chloral hydrate has not been approved by the FDA or the EMA, and is on the list of unapproved drugs that are prescribed for postoperative pain control, sedation and to prevent alcohol withdrawal and reduce anxiety associated with withdrawal of opiates or barbiturates. Mechanism of action of chloral hydrate is not known. It is generally believed that the central depressant effects are due to the principal pharmacologically active metabolite trichloroethanol, which has a plasma half- life of 8 to 10 hours, and acts by potentiating GABA-activated Cl currents.

Lormetazepam (or methyl-lorazepam), possesses hypnotic, anxiolytic, sedative and skeletal muscle relaxant properties. Lormetazepam is not approved for sale in the United States or Canada, though it is licensed in the Netherlands as 1 and 2 mg tablets, under the brand names Loramet and Noctamid and as generic, available from several different manufacturers. Lormetazepam is a short-acting benzodiazepine and is sometimes used in patients who have difficulty in maintaining sleep or falling asleep. Lormetazepam binds to the benzodiazepine receptor which in turn enhances the effect of the GABAA receptor producing its therapeutic effects as well as adverse effects. Lormetazepam appears to be more selective in the type of benzodiazepine receptor it binds to showing a higher affinity for the omega 1 receptor which is responsible for sedation. Changes in electroencephalography can therefore be used to measure the sedative sleep promoting properties of lormetazepam.

Bromisoval (INN; aka bromvalerylurea) is a hypnotic and sedative compound of the bromoureide group discovered by Knoll in 1907 and patented in 1909. It is marketed over the counter in Asia under various trade names (such as Brovarin) usually in combination with non-steroidal anti-inflammatory drugs. Chronic use of bromisoval has been associated with bromine poisoning. Bromovisal can be prepared by bromination of isovaleric acid by the Hell-Volhard-Zelinsky reaction followed by reaction with urea. Bromvalerylurea (BU) can suppress expression of many kinds of pro- and anti-inflammatory mediators in LPS- or interferon-γ activated alveolar and peritoneal macrophages. Bromisoval was found to ameliorate sepsis in rats. It also prevents elevated serum-IL-6 level as well as IL-6 mRNA expression in septic rats. Bromisoval was also found useful for inflammatory skin disorders. The compound is able to suppress the TLR ligands-induced proinflammatory response similar to the steroid DEX without the side effects often associated with the steroid usage.

Brotizolam (marketed under brand name Lendormin) is a sedative-hypnotic thienotriazolodiazepine drug which is a benzodiazepine analog. It possesses anxiolytic, anticonvulsant, hypnotic, sedative and skeletal muscle relaxant properties, and is considered to be similar in effect to short-acting benzodiazepines such as triazolam. It is used in the short-term treatment of severe or debilitating insomnia and in a dose of 0.25 mg can be used as a premedication prior to surgery, this dose was found to be comparable in efficacy to 2 mg flunitrazepam as a premedicant prior to surgery. The drug was developed by a team led by T Nishiyama while working for Takeda Chemical Industries in 1976 in Japan. Brotizolam is not approved for sale in the UK, United States or Canada. It is approved for sale in the Netherlands, Germany, Spain, Belgium, Luxembourg, Austria, Portugal, Israel, Italy, Taiwan and Japan. Insomnia. Brotizolam is prescribed for the short-term treatment, 2–4 weeks only of severe or debilitating insomnia. Insomnia can be described as a difficulty falling asleep, frequent awakening, early awakenings or a combination of each. Brotizolam inhibits the hypothalamus and cerebral limbic system controlling emotion through GABA, a typical inhibitory transmitter of central nervous system. As a result, unnecessary stimulation from the autonomic nervous system and other sites is blocked, demonstrating central nervous action including hypnosis, sedation and anti-anxiety

Allobarbital (5,5-diallylbarbituric acid) is a medium to long-acting barbiturate. It is under international control according to the UN Convention on Psychotropic Substances (Schedule IV). It is used as a sedative and hypnotic and in combination with acetaminophen and codeine as an analgesic. Allobarbital exerts anticonvulsive activity through GABA-ergic mechanisms. Sulfuric derivatives of allobarbital may exert anti-inflammatory activity.

Cyclobarbital (5-cyclohexenyl-5-ethyl-barbituric acid) is a short-acting barbiturate exerting sedative-hypnotic properties. Cyclobarbital is metabolized to inactive ketocyclobarbital. The convention on psychotropic substances, which was signed in Vienna in 1971, today regulates cyclobarbital as a schedule III barbiturate. Cyclobarbital is used in combination with diazepam tranquilizer (Reladorm).

Hexapropymate, a hypnotic/sedative drug that was available without prescription in Belgium under the trade name Merinax for the treatment of insomnia. Poisoning with hexapropymate was a serious condition that required symptomatic treatment in the intensive care unit. As a result, the drug was substituted by newer agents with improved safety profiles.

Flunitrazepam is an intermediate-acting benzodiazepine with general properties similar to those of diazepam. It is generally intended to be for short-term treatment for chronic or severe insomniacs who are unresponsive to other hypnotics. The main pharmacological effects of Flunitrazepam are the enhancement of GABA at the GABAA receptor. The physical effects of Flunitrazepam include sedation, muscle relaxation, decreased anxiety, and prevention of convulsions. It causes partial amnesia; individuals are unable to remember certain events that they experience while under the influence of the drug. Chronic use of Flunitrazepam can result in physical dependence and the appearance of a withdrawal syndrome when the drug is discontinued. Flunitrazepam impairs cognitive and psychomotor functions affecting reaction time and driving skill. The use of this drug in combination with alcohol is a particular concern as both central nervous system depressants potentiate each other's toxicity.

Nitrazepam (trade names: Alodorm, Apodorm, Arem, Mogadon, Nitrados, Nitrazadon, Nitrosun, Ormodon, Paxadorm, Remnos, and Somnite) is a hypnotic drug of the benzodiazepine class, indicated for the short-term relief of severe, disabling anxiety and insomnia. Nitrazepam has sedative and motor-impairing properties, as well as amnestic, anticonvulsant, and skeletal muscle relaxant effects. Nitrazepam is used to treat short-term sleeping problems (insomnia), namely difficulty falling asleep, frequent awakening, early awakening, or a combination of each. Nitrazepam is sometimes tried to treat epilepsy when other medications fail. It has been found to be more effective than clonazepam in the treatment of West syndrome, which is age-dependent epilepsy, affecting the very young. In uncontrolled studies, nitrazepam has shown effectiveness in infantile spasms and is sometimes considered when other anti-seizure drugs have failed. However, drowsiness, hypotonia, and most significantly tolerance to anti-seizure effects typically develop with long-term treatment, generally limiting Nitrazepam to acute seizure management. More common side effects may include: Central nervous system depression, including somnolence, dizziness, depressed mood, rage, violence, fatigue, ataxia, headache, vertigo, impairment of memory, impairment of motor functions, hangover feeling in the morning, slurred speech, decreased physical performance, numbed emotions, reduced alertness, muscle weakness, double vision, and inattention have been reported. Unpleasant dreams and rebound insomnia have also been reported. Nitrazepam is a long-acting benzodiazepine with an elimination half-life of 15–38 hours (mean elimination half-life 26 hours).

Chlormethiazole has sedative, hypnotic, anticonvulsant and neuroprotective properties. This drug is approved in different counties under the different brand name (e.g., Heminevrin) and is used for the management of restlessness and agitation in the elderly, short-term treatment of severe insomnia in the elderly and treatment of alcohol withdrawal symptoms. Clomethiazole interacts with the picrotoxin/barbiturate site of the GABAA-receptor-chloride channel complex. Clomethiazole is pharmacologically distinct from both the benzodiazepines and the barbiturates. Given alone its effects on respiration are slight and the therapeutic index high.