Barbiturates
A class of chemicals derived from barbituric acid or thiobarbituric acid. Many of these are GABA MODULATORS used as HYPNOTICS AND SEDATIVES, as ANESTHETICS, or as ANTICONVULSANTS.
Secobarbital
A barbiturate that is used as a sedative. Secobarbital is reported to have no anti-anxiety activity.
Pentobarbital
A short-acting barbiturate that is effective as a sedative and hypnotic (but not as an anti-anxiety) agent and is usually given orally. It is prescribed more frequently for sleep induction than for sedation but, like similar agents, may lose its effectiveness by the second week of continued administration. (From AMA Drug Evaluations Annual, 1994, p236)
Amobarbital
Thiopental
Barbital
A long-acting barbiturate that depresses most metabolic processes at high doses. It is used as a hypnotic and sedative and may induce dependence. Barbital is also used in veterinary practice for central nervous system depression.
Methohexital
Phenobarbital
Mephobarbital
A barbiturate that is metabolized to PHENOBARBITAL. It has been used for similar purposes, especially in EPILEPSY, but there is no evidence mephobarbital offers any advantage over PHENOBARBITAL.
GABA Modulators
Substances that do not act as agonists or antagonists but do affect the GAMMA-AMINOBUTYRIC ACID receptor-ionophore complex. GABA-A receptors (RECEPTORS, GABA-A) appear to have at least three allosteric sites at which modulators act: a site at which BENZODIAZEPINES act by increasing the opening frequency of GAMMA-AMINOBUTYRIC ACID-activated chloride channels; a site at which BARBITURATES act to prolong the duration of channel opening; and a site at which some steroids may act. GENERAL ANESTHETICS probably act at least partly by potentiating GABAergic responses, but they are not included here.
Hypnotics and Sedatives
Receptors, GABA-A
Thiamylal
Methaqualone
Primidone
An antiepileptic agent related to the barbiturates; it is partly metabolized to PHENOBARBITAL in the body and owes some of its actions to this metabolite. Adverse effects are reported to be more frequent than with PHENOBARBITAL. (From Martindale, The Extra Pharmacopoeia, 30th ed, p309)
Opium
The air-dried exudate from the unripe seed capsule of the opium poppy, Papaver somniferum, or its variant, P. album. It contains a number of alkaloids, but only a few - MORPHINE; CODEINE; and PAPAVERINE - have clinical significance. Opium has been used as an analgesic, antitussive, antidiarrheal, and antispasmodic.
Benzodiazepines
Anesthetics
Meprobamate
A carbamate with hypnotic, sedative, and some muscle relaxant properties, although in therapeutic doses reduction of anxiety rather than a direct effect may be responsible for muscle relaxation. Meprobamate has been reported to have anticonvulsant actions against petit mal seizures, but not against grand mal seizures (which may be exacerbated). It is used in the treatment of ANXIETY DISORDERS, and also for the short-term management of INSOMNIA but has largely been superseded by the BENZODIAZEPINES. (From Martindale, The Extra Pharmacopoeia, 30th ed, p603)
Macedonia (Republic)
Formerly a constituent republic of Yugoslavia, comprising the Yugoslav section of the region of Macedonia. It was made a constituent republic in the 1946 constitution. It became independent on 8 February 1994 and was recognized as The Former Yugoslav Republic of Macedonia by the United States Board on Geographic Names 16 February 1994.
Picrotoxin
A noncompetitive antagonist at GABA-A receptors and thus a convulsant. Picrotoxin blocks the GAMMA-AMINOBUTYRIC ACID-activated chloride ionophore. Although it is most often used as a research tool, it has been used as a CNS stimulant and an antidote in poisoning by CNS depressants, especially the barbiturates.
Diazepam
Phenytoin
An anticonvulsant that is used to treat a wide variety of seizures. It is also an anti-arrhythmic and a muscle relaxant. The mechanism of therapeutic action is not clear, although several cellular actions have been described including effects on ion channels, active transport, and general membrane stabilization. The mechanism of its muscle relaxant effect appears to involve a reduction in the sensitivity of muscle spindles to stretch. Phenytoin has been proposed for several other therapeutic uses, but its use has been limited by its many adverse effects and interactions with other drugs.
Chlormethiazole
A sedative and anticonvulsant often used in the treatment of alcohol withdrawal. Chlormethiazole has also been proposed as a neuroprotective agent. The mechanism of its therapeutic activity is not entirely clear, but it does potentiate GAMMA-AMINOBUTYRIC ACID receptors response and it may also affect glycine receptors.