Cases of overdosage have been reported and rarely, fatalities have occurred. The following signs and symptoms may be observed following overdosage; stupor, coma, diminished urine output and hypotension.
In the event of acute overdosage, the stomach should be emptied by inducing vomiting or by gastric lavage, and the patient carefully observed and given symptomatic and supportive treatment.
Animal studies show that absorption is decreased by the prompt administration of activated charcoal and excretion is enhanced by alkalinization of the urine.