- It is chemically related to the Sulphonamides.
- Acts by inhibition of folate synthesisZ - it is bacteriostatic.
- Resistance to dapsone is increasing , so drug combination is recommended
- it is given orally. Well absorbed.
- widely distrubted through the body water & all tissues.
- plasma half life is 24-48 hours , but it remains in certain tissues to longer periods.
- there is enterohepatic recycling ,but some is acetylated & excreted in urine ,the dose may have to be adjusted in renal failure.
Uses of dapsoneZ
- Leprosy.
- it is used to ttt.of dermatites herpetiforms (chronic blistering skin condition).
- Dapsone may also be used to ttt Pneumocystis carinii pneumonia in AIDS.
Side effects:
- hemolysis of RBCs (usually not severe) , methemoglobinemia , anorexia ,nausea & vomiting.
- Gastrointestinal intolerance ,fever,pruritus & rashes.
- Lepra reaction ( exacerbation of lepromatous lesions ; erythema nodosum leprosum , and potentially fatal may be suppressed bycorticosteroids or by thalidomide).