Rifampicin Celecoxib

Jayasagar G, Krishna Kumar M, Chandrasekhar K, et al. Influence of rifampicin pretreatment on the pharmacokinetics of celecoxib in healthy male volunteers. Drug Metabol Drug Interact 2003 19(4) 287-295. 

NS AIDs RIFAMPICIN Rifampicin L diclofenac, celecoxib, etoricoxib and parecoxib levels Rifampicin T CYP2C9-mediated metabolism of these NSAIDs Monitor analgesic effects consider using alternative NSAIDs... 

The plasma levels of celecoxib, diclofenac, and etoricoxib are reduced by rifampicin. Metamizole (dipyrone) increased the maximum level of rifampicin. Piroxicam appears unaffected by rifampicin. 

In 12 healthy subjects pretreatment with rifampicin 600 mg daily for 5 days reduced the AUC of a single 200-mg dose of celecoxib by 64% and increased the clearance by 185%. A preliminary report of another study found broadly similar results. ... 

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