One patient with hyperventilation later convulsed. In patients on whom details are available, blood pressures have reportedly been normal and pulse rates normal or slightly increased. Abdominal pain, nausea and vomiting have also occurred. EEG changes are similar to those found in mild amphetamine intoxication and withdrawal. Coma, ventricular extrasystoles and ventricular fibrillation may occur at higher dosage.
Treatment consists of supportive measures.
Serious overdosage should be managed with cardiac monitoring, since arrhythmias and cardiac arrest resistant to treatment have been reported. Forced acid diuresis reportedly shortens the duration of symptoms and may be appropriate for severely toxic patients. The value of dialysis has not been established. Initiate therapy at a dosage of 20 mg 3 times daily 1 hour before meals. Therapy should be tailored to the individual need and response of the patient.