ATC Group: N05CM Other hypnotics and sedatives

Clomethiazole has sedative, muscle relaxant and anticonvulsant properties. It is used for hypnosis in elderly and institutionalised patients, for preanaesthetic sedation and especially in the management of withdrawal from ethanol.

Dexmedetomidine is a selective alpha-2 receptor agonist with a broad range of pharmacological properties. It has a sympatholytic effect through decrease of the release of noradrenaline in sympathetic nerve endings. The sedative effects are mediated through decreased firing of locus coeruleus, the predominant noradrenergic nucleus, situated in the brainstem.

Scopolamine is a naturally occurring belladonna alkaloid and has anticholinergic properties. It acts as a competitive antagonist to acetylchloline and other parasympathomimetic agents. Its mechanism of action in the central nervous system in preventing motion sickness has yet to be elucidated. Scopolamine produces classical symptoms of parasympathetic blockade.

Triclofos is a melatonin agonist and has hypnotic and sedative actions similar to those of chloral hydrate, but it is more palatable and causes less gastric irritation. It is converted in the body into an active compound which works in the brain to induce sleepiness. It decreases the time taken to fall asleep and increases sleep duration. It is given by mouth in the short-term management of insomnia.

Valerian is used as a hypnotic, anxiolytic and soothing agent since the oils it contains have a similar effect to benzodiazepines. Its mechanism of action, however, remains largely unknown.