Sulfamethoxazole-trimethoprim side effects, thromocyclopenia oral manifestations


Sulfamethoxazole- trimethoprim (ST) is a sulfonamide derivative antibiotic that interferes with bacterial folic acid synthesis and growth by blocking dihydrofolic acid formation from para-aminobenzoic acid. One of the potential side effects of sulfamethoxazole-trimethoprim is thrombocytopenia. Thrombocytopenia is a blood disorder characterized by a decreased number of circulating platelets. We present two cases of ST induced thrombocytopenia where the oral manifestations were the first indication of the low platelet count leading to life saving interventions. Our aim is to educate dentists about the oral manifestations of thrombocytopenia and its association with ST as their examination may be instrumental in directing treatment.