A depressant, referred to in slang as a "downer," is a chemical agent that diminishes the function or activity of a specific part of the body. (See also sedative.) The term is used in particular with regard to the central nervous system (CNS). Alcohol (consumed in alcoholic beverages) is the most obvious example of a depressant. Many depressants acting on the CNS do so by increasing the activity of a particular neurotransmitter known as gamma-aminobutyric acid (GABA), although other targets such as the NMDA receptor, mu-opioid receptor and CB1 cannabinoid receptor can also be important, depending on which drug is involved. A sedative is a substance that depresses the central nervous system (CNS), resulting in calmness, relaxation, reduction of anxiety, sleepiness, and slowed breathing, as well as slurred speech, staggering gait, poor judgment, and slow, uncertain reflexes. ... A diagram showing the CNS: 1. ... This article does not cite any references or sources. ... Alcoholic beverages are drinks containing ethanol, popularly called alcohol. ... Chemical structure of D-aspartic acid, a common amino acid neurotransmitter. ... Gamma-aminobutyric acid (usually abbreviated to GABA) is an inhibitory neurotransmitter found in the nervous systems of widely divergent species. ... NMDA (N-methyl-D-aspartic acid) is an amino acid derivative acting as a specific agonist at the NMDA receptor, and therefore mimics the action of the neurotransmitter glutamate on that receptor. ... CB1 may refer to: CB postcode area - the Cambridge postcode area Cannabinoid receptor 1 - a receptor for cannabinoids in the brain Category: ...

GABA's task is to calm the CNS and to promote sleep. Drugs that stimulate the activity of this amino acid produce slowed brain function and a drowsy or calm feeling, and so depressants are generally prescribed to relieve symptoms of anxiety or insomnia. Internal systems regulate the body's production of GABA, but when medication is taken to stimulate GABA action, it is possible to induce hazardously high levels, which can dangerously slow breathing and heart rates, and may result in death. Anxiety is a physiological state characterized by cognitive, somatic, emotional, and behavioral components (Seligman, Walker & Rosenhan, 2001). ... This article is about the sleeping disorder. ...

CNS depressants require a period of adaptation. Typically, initial side effects include slurred speech, dizziness, and loss of coordination, in many respects similar to the effects of alcohol.

The most common medically used depressants generally fall into two classes, namely barbiturates and benzodiazepines. Other depressants include alcohol, narcotics (opiate derivatives), sedative-hypnotics, first-generation antihistamines (such as diphenhydramine,) and some anaesthetics (such as ketamine and phencyclidine). Barbiturates are drugs that acts as central nervous system (CNS) depressants, and by virtue of this they produce a wide spectrum of effects, from mild sedation to anesthesia. ... Benzodiazepine tablets The benzodiazepines are a class of drugs with hypnotic, anxiolytic, anticonvulsant, amnestic and muscle relaxant properties. ... An antihistamine is a drug which serves to reduce or eliminate effects mediated by histamine, an endogenous chemical mediator released during allergic reactions, through action at the histamine receptor. ... Diphenhydramine hydrochloride (trade name Benadryl, as produced by J&J, or Dimedrol outside the U.S. & Canada. ... Ketamine is a dissociative anesthetic for use in human and veterinary medicine developed by Parke-Davis (1962). ... “Angel Dust” redirects here. ...

Barbiturates are effective in relieving the conditions they are designed to address; they are also readily abused, physically addictive, and have serious potential for overdose. When, in the late 1960s, it became clear that the social cost of barbiturates was beginning to outweigh the medical benefits, a serious search began for a replacement drug. (See Methaqualone) Most people still using barbiturates today do so in the prevention of seizures or in mild form for relief from the symptoms of migraines. Methaqualone tablets and capsules. ...

Benzodiazepines mediate many of the same symptoms as barbiturates, but are far less toxic and have a strongly reduced risk of overdose. This is not to say they are not without their own risks; where barbiturates pose a greater "front-end" danger in that overdose or drug/alcohol interactions may result in fatality, benzodiazepines pose a greater "back-end" risk in the possibility of addiction, dependence, and serious physical and psychological withdrawal symptoms. Immediate cessation of long-term benzodiazepine use instead of tapering can be dangerous and have serious effects.

Combining multiple depressants is generally recognized as very dangerous because the CNS depressive properties often increase multiplicatively instead of linearly. This characteristic makes depressants a common choice for deliberate overdoses in the case of suicide. The use of alcohol or benzodizepines along with the usual dose of heroin is often the reason of the overdose death of opiates addicted. For other uses, see Suicide (disambiguation). ...

Depressants

The term antipsychotic is applied to a group of drugs used to treat psychosis. ... This article does not cite any references or sources. ... Barbiturates are drugs that acts as central nervous system (CNS) depressants, and by virtue of this they produce a wide spectrum of effects, from mild sedation to anesthesia. ... Benzodiazepine tablets The benzodiazepines are a class of drugs with hypnotic, anxiolytic, anticonvulsant, amnestic and muscle relaxant properties. ... Carisoprodol is a centrally-acting skeletal muscle relaxant whose active metabolite is meprobamate. ... Chloral hydrate, also known as trichloroacetaldehyde monohydrate, 2,2,2-trichloro-1,1-ethanediol, and under the tradenames Aquachloral, Novo-Chlorhydrate, Somnos, Noctec, and Somnote, is a sedative and hypnotic drug as well as a chemical reagent and precursor. ... Dextromethorphan (DXM or DM) is an antitussive (cough-suppressant) drug found in many over-the-counter cold and cough medicines. ... Diphenhydramine hydrochloride (trade name Benadryl, as produced by J&J, or Dimedrol outside the U.S. & Canada. ... Eszopiclone, marketed by Sepracorand marco under the brand-name Lunesta®, is a nonbenzodiazepine hypnotic agent (viz. ... This article is about the chemical compound. ... Ethchlorvynol is a sedative and hypnotic drug. ... Grain alcohol redirects here. ... GHB redirects here. ... Glutethimide is a hypnotic sedative that was introduced in 1954 as a safe alternative to barbiturates to treat insomnia. ... Ketamine is a dissociative anesthetic for use in human and veterinary medicine developed by Parke-Davis (1962). ... A Cannabis sativa plant The drug cannabis, also called marijuana, is produced from parts of the cannabis plant, primarily the cured flowers and gathered trichomes of the female plant. ... Meprobamate (marketed under the brand names Miltown® by Wallace Laboratories and Equanil® by Wyeth) is a carbamate derivative which is used as an anxiolytic drug. ... Methaqualone tablets and capsules. ... Methyprylon is a sedative of the piperidinedione derivative family. ... For other uses, see Nitrous oxide (disambiguation). ... Tiletamine, 2-ethylamino-2-(2-thienyl) cyclohexanone Tiletamine is a dissociative anesthetic chemically and pharmacologically related to other anesthetics in this family such as ketamine and phencyclidine. ... Zaleplon (Sonata®/Starnoc®) is a sedative/hypnotic, mainly used for insomnia. ... Zolpidem is a prescription short-acting nonbenzodiazepine hypnotic that potentiates gamma-aminobutyric acid (GABA), an inhibitory neurotransmitter, by binding to gamma-aminobutyric acid receptors. ... Zopiclone (trade names: Imovane™ and Zimovane™) is a novel hypnotic agent used in the treatment of insomnia. ...

External links

• Painfully Obvious - A Community Resource
• Fact sheets and Harm Reduction Strategies About Depressants and Other Recreational Drugs
• U.S. Department of Human and Health Services: Drug Categories for Substances of Abuse
• About Psychotropic Medications: Quick Reference to Medications Used in Mental Health