barbiturate


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Related to barbiturate: barbiturate coma, barbiturate poisoning

barbiturate

(bärbĭch`ərāt'), any one of a group of drugs that act as depressantsdepressant,
any one of various substances that diminish functional activity, usually by depressing the nervous system. Barbiturates, sedatives, alcohol, and meprobamate are all depressants. Depressants have various modes of action and effects.
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 on the central nervous systemnervous system,
network of specialized tissue that controls actions and reactions of the body and its adjustment to the environment. Virtually all members of the animal kingdom have at least a rudimentary nervous system.
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. High doses depress both nerve and muscle activity and inhibit oxygen consumption in the tissues. In low doses barbiturates act as sedativessedative,
any of a variety of drugs that relieve anxiety. Most sedatives act as mild depressants of the nervous system, lessening general nervous activity or reducing the irritability or activity of a specific organ.
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, i.e., they have a tranquilizing effect; increased doses have a hypnotic or sleep-inducing effect; still larger doses have anticonvulsant and anesthetic activity. The mechanism of action on the central nervous system is not known. The barbiturates are all derivatives of barbituric acid, which was first prepared in 1864 by the German organic chemist Adolf von Baeyer.

The drugs differ widely in the duration of their action, which depends on the rapidity with which they are distributed in body tissues, degraded, and excreted. Ultrashort-acting barbiturates such as thiopental sodium (Pentothal) are often used as general anesthetics. Secobarbital (Seconal) and pentobarbital sodium (Nembutal) are short-acting barbiturates, amobarbital (Amytal) is intermediate in duration of action, and phenobarbital (Luminal) is a long-acting derivative.

Barbiturates are used to relax patients before surgery, as anticonvulsants, and as sleeping pills. They also are commonly abused. Taken regularly, barbiturates can be psychologically and physically addictive (see drug addiction and drug abusedrug addiction and drug abuse,
chronic or habitual use of any chemical substance to alter states of body or mind for other than medically warranted purposes. Traditional definitions of addiction, with their criteria of physical dependence and withdrawal (and often an underlying
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). Barbiturate addicts must be withdrawn from the drug gradually to avoid severe withdrawal symptoms such as convulsions. Overdose can cause coma or death. In the United States the manufacture and distribution of barbiturates were brought under federal control by the 1965 Drug Abuse and Control Act, and they are legally available only by prescription.

Bibliography

See publications of the Drugs & Crime Data Center and Clearinghouse, the Bureau of Justice Statistics Clearinghouse, and the National Clearinghouse for Alcohol and Drug Information.

barbiturate

[bär′bich·ə·rət]
(pharmacology)
Any of a group of ureides, such as phenobarbital, Amytal, or Seconal, that act as central nervous system depressants.

barbiturate

a derivative of barbituric acid, such as phenobarbital, used in medicine as a sedative, hypnotic, or auticonvulsant
References in periodicals archive ?
Organ donation criteria exclude patients whose serum barbiturate concentrations are above a specified level.
Too high a dose of barbiturates can induce permanent sleep.
Activation of calcium-phospholipid-dependent protein-kinase enhances benzodiazepine and barbiturate potentiation of the GABA-A receptor.
Oregon's death with dignity program helps terminally ill patients end their lives simply and painlessly by providing prescriptions for Seconal (a barbiturate) pills which the patient takes himself, according to the Oregon's Health Authority website.
Okamoto M: Barbiturate tolerance and physical dependence: Contribution of pharmacological factors.
But, argues Banzhaf, providing a prisoner with a barbiturate in the form of pills, rather than injecting him with one or more drugs, doesn't seem to require any medical training.
Since most of the reported concerns about using drugs for capital punishment involve problems with injecting the drug, an obvious alternative would be for states to simply use pills rather than injections to administer drugs such as barbiturates, suggests Banzhaf.
Masson et al., "The use of bispectral index to monitor barbiturate coma in severely brain-injured patients with refractory intracranial hypertension," Anesthesia & Analgesia, vol.
A urine barbiturate drug screen was positive (cutoff concentration 300 [micro]g/L).
"Providing a condemned man with barbiturate pills to cause a quick and painless death - as in 'death with dignity' jurisdictions - is well tested, established, and accepted, does not require any trained personnel, and could avoid the many medical problems with injections, as well as restrictions on injectable drugs imposed by many manufacturers because of ethical and moral concerns," suggests Banzhaf.
Phenobarbital (Solfoton[R]), a long-acting barbiturate, produces an anticonvulsant effect as well as sedation and hypnosis by "inhibiting the reticular activating system, thereby increasing the threshold for motor cortex stimulation" (Wilson et al., 2014, p.