[Antibiotic-induced hemorrhagic cystitis].

Two cases of haemorrhagic cystitis following treatment with methicillin and penicillin G are presented. Two males, aged 24 and 45 years, presented identical symptoms including haematuria, dysuria and pollakisuria. The condition has in rare instances been described as caused by antibiotic treatment; in all cases a penicillin was involved. All symptoms promptly vanished when the antibiotic treatment was stopped, and the reactions were possibly allergic since cross-reactions between different penicillins have been described in earlier cases.