Propafenone Rifampicin

RIFAMPICIN PROPAFENONE Rifampicin may l propafenone levels Rifampicin may inhibit CYP3A4/1 A2-mediated metabolism of propafenone Watch for poor response to propafenone... 

Dilger, K., Greiner, B., Fromm, M.F., Flofmann, U., Kroemer, H.K. and Eichelbaum, M. (1999) Consequences of rifampicin treatment on propafenone disposition in extensive and poor metabolizers of CYP2 D6. Pharmacogenetics, 9, 551-559. 

ANTIARRHYTHMICS - disopyramide, propafenone 2. ANTIBIOTICS-chloramphenicol, doxycycline, metronidazole, rifampicin, telithromycin 3. ANTICANCER AND IMMUNOMODULATING DRUGS - carmustine, cidosporin, corticosteroids, doxorubicin, etoposide, ima-tinib, lomustine, paditaxel, tacrolimus, tamoxifen, toremifene, vinca alkaloids 4. ANTICOAGULANTS - ORAL 5. ANTI-... 

As parecoxib is rapidly metabolised to valdecoxib, the interactions are usually considered to be due to the effects of valdecoxib. The manufacturer of parecoxib cautions the concurrent use with carbamazepine, dexamethasone and rifampicin as their effects on parecoxib have not been studied. Valdecoxib increases the levels of dextromethorphan and omeprazole. Because of these interactions, caution is advised with drugs that are metabolised by the same isoenzymes, nameiy flecainide, metoprolol, propafenone, omeprazoie, diazepam, imipramine and phenytoin. No interaction appears to occur between parecoxib and midazolam. 

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