Drug Interaction Report

MONITOR: The concomitant use of local anesthetics and benzodiazepines may have additive CNS-depressant effects. Both types of drugs are CNS depressants. Benzodiazepines administered at the same time raise the threshold for seizures, which is a sign of toxicity for local anesthetics. The data available from manufacturers in different countries is conflicting. Moreover, benzodiazepines (such as diazepam) may be used together with local anesthetics for emergencies in cases of overdosage, while considering the depressive effects benzodiazepines have on respiration and circulation.

MANAGEMENT: Caution is advised during concurrent use. Patients should be monitored for potentially excessive or prolonged CNS depression and other CNS adverse effects. Dosage adjustments may be required. The higher threshold for seizures should be kept in mind when patients receiving these drugs simultaneously are monitored for local anesthetic toxicity.

GENERALLY AVOID: Acute ethanol ingestion may potentiate the CNS effects of many benzodiazepines. Tolerance may develop with chronic ethanol use. The mechanism may be decreased clearance of the benzodiazepines because of CYP450 hepatic enzyme inhibition. Also, it has been suggested that the cognitive deficits induced by benzodiazepines may be increased in patients who chronically consume large amounts of alcohol.

MANAGEMENT: Patients should be advised to avoid alcohol during benzodiazepine therapy.