Тиопентал натрия

Химические свойства

Yellowish-white, hygroscopic powder.

Использование

Pentothal (Abbott).

Определение

A rapidly acting barbiturate administered intravenously for general anesthesia and hypnosis. Commonly known as “truth serum.”

Опасность

May cause respiratory failure; use onlywith physician in attendance.

Фармакокине?тика

Thiopental is highly bound to albumin, and free drug availability is increased in hypoproteinaemia. Protein binding is decreased by alkalaemia, hyperventilation and some drugs that occupy the same albumin binding sites, thereby increasing unbound thiopental concentrations. Metabolism occurs predominantly in the liver, and the metabolites are excreted by the kidneys. Only a small proportion is excreted unchanged in the urine. The terminal elimination half-life is approximately 11.5h (longer in the elderly). Elimination after an infusion is a zero-order process with 10%–15% of the remaining drug metabolised each hour. Up to 30% of the original dose may remain in the body at 24h, and a hangover effect is common. Accumulation may result if further doses of thiopental are administered within 1–2 days.

Профиль безопасности

Poison by ingestion, intraperitoneal, rectal, subcutaneous, and intravenous routes. Human systemic effects by intraarterial route: acute arterial occlusion; by rectal route: respiratory depression, body temperature decrease, general anesthetic. An experimental teratogen. Experimental reproductive effects. An intravenous anesthetic. When heated to decomposition it emits toxic fumes of NO, and Na2O. See also PENTOTHAL and BARBITURATES