Major Drugs Acting on the Central Nervous System

Abstract

In general, the rate of allergic reactions to general anesthetics is low. However, the drug halothane (2-bromo-2-chloro-1,1,1-trifluoroethane), which was introduced into clinical pharmacologic use as a general anesthetic in 1956, has been strongly suspected of causing an allergic hepatitis. Moult and Sherlock (1975) reported a series of 26 patients who developed postoperative jaundice following the use of this agent and in whom no other cause for liver disease could be found. In accord with previous reports, the clinical picture was primarily that of an acute hepatitis with hepatocellular dysfunction, developing a few days to several weeks after halothane anesthesia. Halothane-induced hepatitis usually occurs in a patient who has been exposed previously to the same agent. In Moult and Sherlock’s series, out of 26 patients, 24 had received halothane more than once, and 18 had had it twice within a 4-week period. The development of sensitivity may be suspected if there has been an unexplained episode of fever within 1–2 weeks following previous halothane use. Unexplained jaundice or delayed fever after a previous administration of halothane should be considered contraindications to futher use (Moult and Sherlock 1975). However, while multiple exposures to halothane within the same 4-week period appear to be particularly hazardous, even in this situation the risk of jaundice is probably no greater than 1–3 in 6,000 patients.