Pentothal

Pentothal is the brand name for sodium thiopental, a short-acting intravenous barbiturate used primarily as an induction agent for general anesthesia. It is valued for its rapid onset of unconsciousness, typically within 30 seconds after IV administration, and its very brief duration of action, around 5 to 20 minutes, due to rapid redistribution from the brain to body tissues.

Pharmacology and mechanism of action: Thiopental is a highly lipophilic drug that enhances the activity of the gamma-aminobutyric acid type A (GABA-A) receptor, producing central nervous system depression. Its ultra-short duration is largely a result of rapid redistribution rather than fast metabolism. It is metabolized in the liver and eliminated largely by the kidneys. While it produces anesthesia, it does not provide analgesia.

Medical uses: Pentothal is used to induce general anesthesia and to facilitate rapid sequence intubation in various surgical and diagnostic procedures. It has also been used as an adjunct in electroconvulsive therapy anesthesia. In some jurisdictions, thiopental has historically been used as the unconsciousness-inducing drug in capital punishment protocols, though its use in this context has declined and varies by country and state.

Side effects and safety: Common adverse effects include hypotension and respiratory depression, which can lead to apnea and airway compromise if not carefully managed. Nausea, vomiting, and temporary postoperative dizziness may occur. Thiopental can precipitate porphyria in susceptible individuals and should be avoided in such patients. It is not an analgesic and may interact with other central nervous system depressants, alcohol, and certain cardiovascular medications.

History and status: Introduced in the 1930s and marketed under the Pentothal brand, thiopental played a major role in anesthesia practice for decades. In many countries, its routine use has declined in favor of other induction agents such as propofol, though it remains available in some settings and for specific indications.