pharm leprosy Flashcards
Dapsone MOA
Folate antagonist producing bacteriostatic effect
-inhib. of 2nd mesenger pathways involved in neutrophil chemotaxis
which anti-leprosy do you have to avoid in G6PD deficiency?
dapsone
dapsone is metabolized to hydroxylamine which is a potenet oxidant that can cause what 2 important and adverse effects?
methemoglobinemia
hemolysis
what are the important drug interactions with dapsone?
rifampin–> increased toxicity
cimetidine & omeprazole–> decreased toxicity
what happens if you give dapsone with probenicid?
leads to decreased clearance and subsequent accumulation
how is dapsone eliminated?
renal, RENAL FUNCTION IS IMPORTANT
what is dapsone syndrome?
adverse effects of dapsone therapy including: rash on upper limbs and forehead, dermatitis and LAD
- hemolysis
- methemoglobinemia
- hepatitis
- cholestatic jaundice
- peripheral neuropathy
- severe hypoalbuminemia
which 2 adverse effects of dapsone syndrome are reversible?
hemolysis and hepatitis
what are the on label uses of dapsone?
Leprosy (hansen’s disease)
acne vulgaris
dermatitis herpetiformis
MOA of rifampin
inhibits bacterial & mycobacterial RNA synth. by binding to the beta-subunit of the DNA-dependent RNA polymerase
how is rifampin distributed in the body?
widely distributed
-crosses inflamed meninges, placenta, into breastmilk
whats unique about the metabolism and elimination of rifampin?
undergoes enterohepatic cycling
what are the major adverse effects of rifampin?
severe liver toxicity
turns body fluids orange red (ruins contact lenses)
how does clofazimine work?
preferential binding to mycobacterial guanine and cytosine in DNA
-much more G & C in mycobacterium than human DNA
which antileprosy drug is highly lipophilic and persists for a long time in fatty tissues and the RES?
Clofazamine
