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Information about Depressant

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.

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.

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 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.

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 due to the fact that 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.

Depressants/Downers

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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.
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The central nervous system (CNS) represents the largest part of the nervous system, including the brain and the spinal cord. Together with the peripheral nervous system, it has a fundamental role in the control of behavior.
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alcohol is any organic compound in which a hydroxyl group (-OH) is bound to a carbon atom of an alkyl or substituted alkyl group. The general formula for a simple acyclic alcohol is CnH2n+1OH.
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An alcoholic beverage (also known as booze in slang term) is a drink containing ethanol, commonly known as alcohol, although in chemistry the definition of alcohol includes many other compounds.
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Neurotransmitters are chemicals that are used to relay, amplify and modulate signals between a neuron and another cell. According to the prevailing beliefs of the 1960s, a chemical can be classified as a neurotransmitter if it meets the following conditions:

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Gamma-aminobutyric acid (usually abbreviated to GABA) is an inhibitory neurotransmitter found in the nervous systems of widely divergent species. It is the chief inhibitory neurotransmitter in the central nervous system and also in the retina.
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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.
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CB1 may refer to:
  • CB postcode area - the Cambridge postcode area
  • Cannabinoid receptor 1 - a receptor for cannabinoids in the brain

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Anxiety is a physiological state characterized by cognitive, somatic, emotional, and behavioral components (Seligman, Walker & Rosenhan, 2001). These components combine to create the feelings that we typically recognize as fear, apprehension, or worry.
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MeSH D007319

Insomnia is a sleeping disorder characterized by the inability to fall asleep and/or the inability to remain asleep for a reasonable amount of time.
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Barbiturates are drugs that act as central nervous system depressants, and by virtue of this they produce a wide spectrum of effects, from mild sedation to anesthesia. Some are also used as anticonvulsants.

Barbiturates are derivatives of barbituric acid.
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The benzodiazepines (pronounced [ˌbɛnzəʊdaɪˈæzəpiːnz], or "benzos" for short) are a class of psychoactive drugs considered minor tranquilizers with varying hypnotic, sedative, anxiolytic,
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This article or section may be confusing or unclear for some readers.
Please [improve the article] or discuss this issue on the talk page. This article has been tagged since September 2007.
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Indicated for:
  • Antihistaminic
  • Motion sickness
  • Sedative/Hypnotic
Other uses:
  • Halting allergic reactions, controlling extrapyramidal side-effects induced by antipsychotics
Contraindications:

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Ketamine is a dissociative anesthetic for use in human and veterinary medicine developed by Parke-Davis (1962). Its hydrochloride salt is sold as Ketanest, Ketaset, and Ketalar.
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Phencyclidine (a contraction of the chemical name phenylcyclohexylpiperidine), abbreviated PCP, is a dissociative drug formerly used as an anesthetic agent, exhibiting hallucinogenic and neurotoxic effects.
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Methaqualone1 is a sedative drug which is similar in effect to barbiturates, a general CNS depressant. It was used in the 1960s and 1970s as an anxiolytic, for the treatment of insomnia, and as a sedative and muscle relaxant.
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Migraine
Classification & external resources

ICD-10 G 43.
ICD-9 346

OMIM 157300
DiseasesDB 8207
MedlinePlus 000709
eMedicine neuro/218  
MeSH D008881

Migraine
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Suicide (Latin sui caedere, to kill oneself) or Self-murder, is the act of intentionally terminating one's own life. Suicide occurs for a number of reasons such as depression, substance abuse, shame, avoiding pain, financial difficulties or other undesirable fates.
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The term antipsychotic is applied to a group of drugs used to treat psychosis. Common conditions with which antipsychotics might be used include schizophrenia, mania and delusional disorder.
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alcohol is any organic compound in which a hydroxyl group (-OH) is bound to a carbon atom of an alkyl or substituted alkyl group. The general formula for a simple acyclic alcohol is CnH2n+1OH.
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Barbiturates are drugs that act as central nervous system depressants, and by virtue of this they produce a wide spectrum of effects, from mild sedation to anesthesia. Some are also used as anticonvulsants.

Barbiturates are derivatives of barbituric acid.
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The benzodiazepines (pronounced [ˌbɛnzəʊdaɪˈæzəpiːnz], or "benzos" for short) are a class of psychoactive drugs considered minor tranquilizers with varying hypnotic, sedative, anxiolytic,
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Carisoprodol is a centrally-acting skeletal muscle relaxant whose active metabolite is meprobamate. Although several case reports have shown that carisoprodol has abuse potential[1]
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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
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Dextromethorphan (DXM or DM) is an antitussive (cough-suppressant) drug found in many over-the-counter cold and cough medicines. Dextromethorphan has also found other uses in medicine, ranging from pain relief to psychological applications.
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Indicated for:
  • Antihistaminic
  • Motion sickness
  • Sedative/Hypnotic
Other uses:
  • Halting allergic reactions, controlling extrapyramidal side-effects induced by antipsychotics
Contraindications:

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Eszopiclone, marketed by Sepracor under the brand-name Lunesta, is a nonbenzodiazepine hypnotic agent (viz., a sedative) used as a treatment for insomnia. Eszopiclone is the active stereoisomer of zopiclone, and belongs to the class of drugs known as cyclopyrrones.
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Diethyl ether, also known as ether and ethoxyethane, is a clear, colorless, and highly flammable liquid with a low boiling point and a characteristic smell. It is the most common member of a class of chemical compounds known generically as ethers.
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Ethchlorvynol is a sedative and hypnotic drug. It has been used to treat insomnia, but has been largely superseded and is only offered where an intolerance or allergy to other drugs exists.
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