Serious adverse reactions: Fatalities associated with the administration of sulphonamides and trimethoprim, either alone or in combination, have occurred due to severe reactions, including Stevens-Johnson syndrome, toxic epidermal necrolysis, fulminant hepatic necrosis, agranulocytosis, aplastic anaemia, other blood dyscrasias, hypersensitivity of the respiratory tract and other reactions. The drug should be discontinued at the first appearance of skin rash or any sign of adverse reaction.