Item |
Information |
Drug Groups
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approved |
Description
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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) |
Indication |
For the short-term treatment of insomnia. |
Pharmacology |
Pentobarbital, a barbiturate, is used for the treatment of short term insomnia. It belongs to a group of medicines called central nervous system (CNS) depressants that induce drowsiness and relieve tension or nervousness. Little analgesia is conferred by barbiturates; their use in the presence of pain may result in excitation. |
Toxicity |
Symptoms of an overdose typically include sluggishness, incoordination, difficulty in thinking, slowness of speech, faulty judgment, drowsiness or coma, shallow breathing, staggering, and in severe cases coma and death. |
Affected Organisms |
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Humans and other mammals |
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Biotransformation |
by hepatic microsomal enzyme system |
Absorption |
Barbiturates are absorbed in varying degrees following oral, rectal, or parenteral administration. |
Half Life |
5 to 50 hours (dose dependent) |
Elimination |
Barbiturates are metabolized primarily by the hepatic microsomal enzyme system, and the metabolic products are excreted in the urine, and less commonly, in the feces. Approximately 25 to 50 percent of a dose of aprobarbital or phenobarbital is eliminated unchanged in the urine, whereas the amount of other barbiturates excreted unchanged in the urine is negligible. |
References |
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Knodell RG, Spector MH, Brooks DA, Keller FX, Kyner WT: Alterations in pentobarbital pharmacokinetics in response to parenteral and enteral alimentation in the rat. Gastroenterology. 1980 Dec;79(6):1211-6.
[Pubmed]
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External Links |
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