sedativehypnotics

Sedative-hypnotics are a class of drugs that depress the central nervous system to produce calming effects (sedation) and sleep-inducing effects (hypnosis). They are used for conditions such as anxiety, insomnia, pre-anesthetic medication, and sometimes seizure control. The primary mechanism for many classic sedative-hypnotics is enhancement of the GABA-A receptor, which increases inhibitory neurotransmission in the brain. They include benzodiazepines (for example diazepam, temazepam, lorazepam), nonbenzodiazepine hypnotics commonly called Z-drugs (zolpidem, zaleplon, eszopiclone), and older barbiturates (phenobarbital, pentobarbital). Other agents with sedative-hypnotic activity include ramelteon (a melatonin receptor agonist) and suvorexant (an orexin receptor antagonist), though they differ in mechanism and safety profile.

Indications typically include short-term management of insomnia, treatment of anxiety disorders under medical supervision, and use in anesthesia or acute agitation. Safety concerns are substantial and include tolerance, dependence, and withdrawal with long-term use; cognitive and psychomotor impairment; daytime sleepiness; falls in older adults; and the risk of respiratory depression when combined with alcohol or opioids. Barbiturates carry a higher overdose risk and more dangerous withdrawal than benzodiazepines or nonbenzodiazepine hypnotics and are used less frequently. Nonbenzodiazepine hypnotics generally have a lower risk of dependence but can still be misused. Safe use requires medical oversight, appropriate dosing, and consideration of comorbidities.

Withdrawal symptoms can include insomnia, anxiety, tremor, and, in severe cases, seizures. Drug interactions with other central nervous system depressants and with liver-enzyme inhibitors or inducers can alter effects. Sedative-hypnotics are subject to regulatory controls varying by country.