Balanitis due to fixed drug eruption associated with tetracycline therapy.

An eruption is called 'fixed' if it recurs at the same site after re-exposure to the drug which precipitated the previous lesion. The eruption is commonly erythematous and sharply defined but may be bullous, herpetiform, or urticarial, and can be solitary or widely scattered. The commonest target areas are the trunk and the proximal portions of the limbs and the mouth, eyes, and urethra may sometimes be involved. Recently we observed five patients who developed a fixed eruption on the glans penis after oral tetra-cycline treatment for non-gonococcal urethritis (NGU). No similar instances have been found in the available literature and as such cases may give rise to diagnostic difficulties, the histories are reported below. Case reports Case 1, a single Caucasian male teacher aged 24, attended the special clinic from March 1968 to July 1969, with recurrent non-gonococcal urethritis. He gave a history of NGU in 1967; there had been no other significant illness and there were no known allergies. During the period of attendance he had six separate episodes of NGU, each of which was treated with tetracycline 250 mg. four times daily for 5 days to which the urethritis responded. During the fourth attack he developed a circumscribed irritating herpetiform eruption on the glans penis a few hours after starting treatment. The lesion became worse over the next 5 days and then cleared rapidly. A diagnosis of NGU with probable herpes genitalis was made. A further attack of NGU occurred 4 months later and after treatment was started the same sequence of events was noted except that the lesion on the glans was erythe-matous. A month later another episode of NGU brought him to the clinic and this time we considered the possibility that he was subject to a fixed eruption due to tetracycline. To prove this we obtained permission from the patient to give him tetracycline and to observe the effects; within 3 hours of the first dose of tetracycline an erythematous area developed on the glans penis at the same site as before (Figure). The urethritis cleared within 7 days and so did the eruption. During the period of attendance the patient had not taken any other drugs. FIG U R E Case 1. Fixed drug eruption on glans penis following 250 mg. tetracycline Case 2, a married Caucasian policeman aged 29, attended the clinic from June to August 1969, and gave a history of …