Assessment | Biopsychology | Comparative | Cognitive | Developmental | Language | Individual differences | Personality | Philosophy | Social |
Methods | Statistics | Clinical | Educational | Industrial | Professional items | World psychology |

Biological: Behavioural genetics · Evolutionary psychology · Neuroanatomy · Neurochemistry · Neuroendocrinology · Neuroscience · Psychoneuroimmunology · Physiological Psychology · Psychopharmacology (Index, Outline)

This article is in need of attention from a psychologist/academic expert on the subject.
Please help recruit one, or improve this page yourself if you are qualified.
This banner appears on articles that are weak and whose contents should be approached with academic caution


CNS depressant drugs are drugs that produce central nervous system depression which refers to physiological depression of the central nervous system that can result in decreased rate of breathing, decreased heart rate. In overdose they can lead to a loss of consciousness possibly leading to coma or death.

Specific drugs include:

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.

GABA's task is to calm the CNS and to promote sleep. Drugs that stimulate the activity of this 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.

CNS depressants require a period of adaptation. Typically, initial side effects include slurred speech, dizziness, and loss of coordination.

Types[edit | edit source]

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).

Alcohol[edit | edit source]

Main article: Alcoholic Beverage
Main article: Ethanol
Main article: Blood Alcohol Content

Distilled (concentrated) alcoholic beverages, often called "hard liquor", roughly eight times more alcoholic than beer

Barbiturates[edit | edit source]

Main article: Barbiturates

Barbiturates are effective in relieving the conditions that they are designed to address. They are also commonly misused, physically addictive, and have serious potential for overdose. When, in the late 1950s, it became clear that the social cost of barbiturates was beginning to outweigh the medical benefits, a serious search began for a replacement drug. Most people still using barbiturates today do so in the prevention of seizures or in mild form for relief from the symptoms of migraines.

Benzodiazepines[edit | edit source]

Main article: Benzodiazepines

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.

Cannabis[edit | edit source]

Main article: Cannabis

Although Cannabis or Marijuana is often considered either in its own unique category or as a mild psychedelic, the drug, notably the chemical compound Cannabidiol in it, still does nevertheless have many depressant effects such as muscle relaxation, sedation, decreased alertness, and tiredness.

Opioids[edit | edit source]

Main article: Opioid

Miscellaneous[edit | edit source]

Combinations[edit | edit source]

Combining multiple depressants can be very dangerous because the central nervous system's depressive properties has been proposed to increase exponentially instead of linearly.[citation needed] This characteristic makes depressants a common choice for deliberate overdoses in the case of suicide. The use of alcohol or benzodiazepines along with the usual dose of heroin is often the cause of overdose deaths in opiate addicts.

See also[edit | edit source]

Consider including[edit | edit source]

This page uses Creative Commons Licensed content from Wikipedia (view authors).
Community content is available under CC-BY-SA unless otherwise noted.