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.