[Cimetidine in treatment of acute intermittent porphyria]

Two female patients with repeated exacerbations of acute intermittent porphyria (20 exacerbations in 44 and 5 in 34 months, respectively) were treated with cimetidine (2 x 400 mg/d) over 4 months. Therapeutical aim of the medication was to prevent further porphyria manifestations. In contrast to previous casuistic reports and experimental studies in laboratory animals cimetidine did not stabilize porphyrin biosynthesis. One patient had an acute attack during the period of treatment, while the other had no further exacerbations. However, cimetidine did not worsen the clinical course of our patients either and therefore can safely be applied as an H2-antagonist in patients with acute intermittent porphyria. While administration of glucose and heme-preparations is considered to be an effective form of therapy for the acute episodes, long-lasting as well as prophylactic therapies in order to stabilize the period of remission are not known so far.