Indications: relieving ischaemia and symptoms of senile dementia but its value is doubtful; impotence. Although not licensed the smooth muscle relaxant papaverine has also been given by intracavernosal injection for erectile dysfunction. Patients with neurological or psychogenic impotence are more sensitive to the effect of papaverine than those with vascular abnormalities. Phentolamine is added if the response is inadequate Persistence of the erection for longer than 4 hours is an emergency.

Cautions: intravenous injection can cause cardiac arrhythmias; glaucoma; depressed myocardial function.

Contra-indications: complete atrioventricular block.

Side Effects: gastro-intestinal disturbance, flushing of the face, headache, malaise, drowsiness, skin rash, sweating and vertigo; hypersensitivity reactions.

Dose: impotence, by intra-cavernosal injection, 30mg together with phentolamine 1mg.