sedatives

Sedatives are substances that depress central nervous system activity, producing calmness, reduced anxiety, and often drowsiness. They are used to alleviate agitation, facilitate sleep, or prepare a patient for medical procedures. The term covers a range of drugs; sedatives lower arousal without necessarily inducing sleep, while hypnotics are more likely to promote sleep.

Most traditional sedatives act by enhancing the effects of gamma-aminobutyric acid (GABA), the brain’s main inhibitory neurotransmitter, on its receptors, which dampens neuronal firing. Drug classes include benzodiazepines (such as diazepam, lorazepam, temazepam), barbiturates (phenobarbital), and non-benzodiazepine hypnotics (zolpidem, zaleplon, eszopiclone). Other agents with sedative properties are certain antihistamines (diphenhydramine), as well as sedative drugs used in anesthesia and critical care (propofol, dexmedetomidine).

Medical uses encompass short-term relief of anxiety, treatment of insomnia when other measures have failed, and various forms of procedural or preoperative sedation. They may be employed for induction of anesthesia or for sedation in intensive care, depending on the agent and clinical context. Dosing, onset, and duration vary widely among drug classes.

Safety and regulation are important considerations. Sedatives can cause dependence and tolerance with long-term use, and withdrawal can be hazardous. Side effects include daytime drowsiness, cognitive impairment, and, in higher doses or when combined with alcohol or opioids, respiratory depression. Other risks include falls in the elderly and potential interactions with other medications. Because many sedatives are prescription-only and controlled substances, they require careful medical oversight.