Aims: To quantify the risk of serious blood and skin disorders requiring hospitalization among otherwise healthy users of co-trimoxazole.
Methods: We conducted a population-based cohort study at Group Health Cooperative of Puget Sound (GHC).
Results: During the years 1987 to 1993 we found six cases of co-trimoxazole-associated blood disorders and three cases of co-trimoxazole-associated skin disorders yielding risks of 5.6/100,000 (95% CI 2.6-12.2) and 2.8/100,000 (95% CI 0.9-8.2) respectively. In all cases found there was prompt recovery after discontinuation of co-trimoxazole. We found no cases of toxic epidermal necrolysis.
Conclusions: We conclude that the risk of blood and skin disorders associated with the use of co-trimoxazole leading to hospitalization is low.