Lidocaine metabolism and toxicity: a laboratory experiment for dental students.

A laboratory exercise for dental students based on a modification of the classical pentobarbital sleeping-time experiment is presented. The substitution of a toxic dose of lidocaine in place of an anesthetic dose of pentobarbital allows demonstration of the same general principles of drug metabolism, i.e., induction of the hepatic drug metabolizing systems by phenobarbital, reduction of hepatic drug metabolism by liver damage or disease, or both, and the relationship between the rate of drug detoxification and the duration and intensity of drug effects. However, the use of lidocaine demonstrates its toxic and lethal actions and increases the relevance of the experience for dental students.