A variety of neurological toxic effects and malignant hyperpyrexia can occur, sometimes with fatal results. Amphetamines may counteract the sedative effect of antihistamines. Chlorpromazine blocks dopamine and norepinephrine reuptake, thus inhibiting the central stimulant effects of amphetamines, and can be used to treat amphetamine poisoning. Amphetamines may delay intestinal absorption of ethosuximide. Haloperidol blocks dopamine and norepinephrine reuptake, thus inhibiting the central stimulant effects of amphetamines.
Amphetamines potentiate the analgesic effect of meperidine.
Amphetamines enhance the adrenergic effect of norepinephrine. In most cases of propoxyphene overdosage, amphetamine CNS stimulation is potential and fatal convulsions can occur. Amphetamines inhibit the hypertensive effect of veratrum alkaloids. There have been isolated reports of cardiomyopathy associated with chronic amphetamine use. Dryness of the mouth, unpleasant taste, diarrhea, constipation, other gastrointestinal disturbances.