N-hydroxylamine Dapsone is an active metabolite of dapsone .¹It is formedviaN-hydroxylation of dapsone by the cytochrome P450 (CYP) isoforms CYP2C8, CYP2C9, CYP2C18, and CYP2C19 in the liver.²N-hydroxylamine Dapsone is cytotoxic to rat hepatocytes (LC₅₀= 3.6 mM).³It induces hemolysis in isolated human erythrocytes at a concentration of 100 µM.¹N-hydroxylamine Dapsone induces phosphatidylserine (PS) exposure on the outer membrane, a marker of apoptosis and platelet activation, and increases the production of reactive oxygen species (ROS) in a concentration-dependent manner in isolated human erythrocytes. It increases thrombus weight in a rat model of surgically induced thrombosis when administered at a single dose of 50 mg/kg or at a dose of 10 mg/kg per day for four days.

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