[Adverse effects of Disulone; results of the France pharmacovigilance inquiry. Regional Centers of Pharmacovigilance].

Disulone (dapsone + ferrous oxalate) is a sulphone marketed in France since 1958 and authorized in P. Carinii prophylaxis in HIV+ cotrimoxazole intolerant patients, bullous dermatosis, leprosy and polychondritis. Between 1983 and 1998, 249 adverse reactions were reported to French pharmacovigilance centres and Aventis, the manufacturer. Every side-effect was reviewed and the causal relationship was assessed on the basis of the French method for causality assessment. Main side-effects were divided as follows: 117 blood dyscrasias (generally neutropenia and agranulocytosis, rarely methaemoglobinaemia, haemolysis, macrocytosis, anaemia, aplastic anaemia, haemochromatosis and sulphaemoglobinaemia); 29 hypersensitivity syndrome; 39 cutaneous reactions, generally rash; 27 liver injuries (cholestatic, cytolytic and mixed hepatitis); 27 neurological and psychiatric side-effects including 7 axonal neuropathy; 10 gastrointestinal effects, generally nausea and vomiting. Five deaths were reported (4 septicaemia including one case not due to dapsone and 1 digestive bleeding due to underlying disease). In the other cases the outcome was favourable. The results were compared with the published references. It would seem to be important to reinforce information to prescribers about the possible serious adverse reactions with dapsone, particularly hypersensitivity syndrome and agranulocytosis, that can cause death if the drug is not stopped in time.