Manifestations of acute overdosage may include restlessness, tremor, hyperreflexia,
rapid respiration, confusion, assaultiveness, hallucinations, panic states.
Fatigue and depression usually follow the central stimulation.
Cardiovascular effects include arrhythmias, hypertension, or hypotension and
circulatory collapse. Gastrointestinal symptoms include nausea, vomiting, diarrhea,
and abdominal cramps. Overdosage of pharmacologically similar compounds has
resulted in fatal poisoning, usually terminating in convulsions and coma.
Management of acute IONAMIN (phentermine resin complex) intoxication is largely symptomatic and includes
lavage and sedation with a barbiturate. Experience with hemodialysis or peritoneal
dialysis is inadequate to permit recommendation in this regard. Intravenous
phentolamine (Regitine) has been suggested on pharmacologic grounds for possible
acute, severe hypertension, if this complicates overdosage.