Tolerance to intravenous midazolam as a result of oral benzodiazepine therapy: a potential problem for the provision of conscious sedation in dentistry.

Tolerance to the sedative effects of the benzodiazepine group of drugs is well documented. A brief review of the literature is presented. Three cases in which tolerance to intravenous midazolam became apparent and caused a significant problem during the attempted induction of conscious sedation are described. The patients were all concurrently receiving treatment with other benzodiazepines. It is recommended that patients with a history of regular, current benzodiazepine use be treated with caution with regard to this type of sedation.