Benzodiazepines commonly cause drowsiness, ataxia, dysarthria and nystagmus. Coma, hypotension and respiratory depression occasionally occur but are seldom serious if these drugs are taken alone. Coma usually lasts only a few hours but in elderly people it may be more protracted and cyclical. Benzodiazepine respiratory depressant effects are more serious in patients with severe chronic respiratory disease.

Benzodiazepines potentiate the effects of other central nervous system depressants, including alcohol.

Management
Consider activated charcoal in adults or children who have taken more than 1 mg/kg within 1 hour, provided they are not too drowsy. Gastric lavage is unnecessary if these drugs have been taken alone. Patients who are asymptomatic at four hours are unlikely to develop symptoms. Institute supportive measures as indicated by the patient's clinical state.

If CNS depression is severe consider the use of flumazenil (Anexate), a benzodiazepine antagonist. This should rarely be required. It has a short half-life (about an hour) and should NOT TO BE USED IN MIXED OVERDOSE OR AS A "DIAGNOSTIC" TEST. It is contraindicated in the presence of drugs that reduce seizure threshold (e.g. tricyclic antidepressants).


Page last modified: 19 September 2005