Propafenone drug interactions

Drug interactions Catecholamine-depleting drugs such as reserpine may have an additive effect in combination with betablockers. Drugs that inhibit CYP2D6 (quinidine, fluoxetine, paroxetine, and propafenone) increase metoprolol concentration. 

Wagner F, Kalushce D, Trenk D, et al. Drug interaction between propafenone and metoprolol. Br J Clin Pharmacol 1987 24 213-220. 

Genetic differences can also influence the likelihood of some drug interactions. For example, coadministration of the antiarrhythmic propafenone to patients being treated with metoprolol substantially reduces metoprolol metabolic clearance in extensive... 

The calcium channel blocker mibefradil (Posicor ) was removed from the market in 1998. The headline for the Pink Sheets article describing this action was "Posicor Withdrawal Reflects Complexity of Interaction Profile" (59). Products identified as potentially dangerous in combination with mibefradil included cardiac drugs, such as amiodarone, flecainide, and propafenone oncologic products, such as tamoxifen, cyclophosphamide, etoposide, ifosfamide, and vinblastine and the immunosuppressant medications cyclosporine and tacrolimus. The sponsor s decision to withdraw mibefradil was based on the complexity of the drug interaction information that would have to be communicated to ensure safe usage. 

Lee, B. L. and Dohrmann, M. L., Theophylline toxicity after propafenone treatment evidence for drug interaction, Clin. Pharmacol. Then, 51(3) 353-355, 1992. 

Beyond those in vivo examples depicted in Table 4, there are some in vitro data suggesting stereoselective drug interactions with oral anticoagulants. For example, Hermans and Thijssen [68] investigated the potential of metabolic interactions in vitro between warfarin or acenocou-marol and cimetidine, propafenone, sulphaphenazole, or omeprazole using human liver microsomes. Sulphaphenazole competitively inhibited the 7- and in some experiments the 6-hydroxylation of S-warfarin and R- and S-acenocoumarol. Omeprazole partly inhibited the 6- and 7-hydroxylation of R-warfarin, R-acenocoumarol, and S-acenocoumarol [68]. 

An established and clinically relevant metabolic drug interaction. The dosage of oral propafenone will need increasing during concurrent use of ri-fampicin. Alternatively, if possible, the authors of the case report advise the use of another antibacterial, where possible, because of the probable difficulty in adjusting the propafenone dosage. 

Drug-drug interactions Verapamil Verapamil may have precipitated propafenone toxicity [67 ]. 

Lopinavir/Ritonavir (Kaletra) [Anrirelroviral/Protease Inhibitor] Uses HIV Infxn Action Protease inhibitor Dose Adults. Tx naive 2 tab PO daily or 1 tab PO bid Tx experiencedpt 1 tab PO bid (T dose if w/ amprenavir, efavirenz, fosamprenavir, nelfinavir, nevirapine) Peds. 7-15 kg 12/3 mg/kg PO bid 15-40 kg 10/2.5 mg/kg PO bid >40 kg Adult dose w/ food Caution [C, /-] Numerous interactions Contra w/drugs dependent on CYP3A/CYP2D6 (Table VI-8) Disp Tab, soln SE Avoid disulfiram (soln has EtOH), metronidazole GI upset, asthenia, T cholesterol/triglycerides, pancreatitis protease metabolic synd Interactions T Effects Wl clarithromycin, erythromycin T effects OF amiodarone, amprenavir, azole andfungals, bepridil, cisapride, cyclosporine, CCBs, ergot alkaloids, flecainide, flurazepam, HMG-CoA reductase inhibitors, indinavir, lidocaine, meperidine, midazolam, pimozide, propafenone, propoxyphene, quinidine, rifabutin, saquinavir, sildenafil, tacrolimus, terfenadine, triazolam, zolpidem 1 effects Wl barbiturates, carbamazepine, dexamethasone, didanosine, efavirenz, nevirapine, phenytoin, rifabutin, rifampin, St. John s wort 1 effects OF OCPs, warfarin EMS Use andarrhythmics and benzodiazepines... 

C. Funck-Brentano, H. K. Kroemer, H. Pavlou, R. L. Woosley and D. M. Roden, "Genetically-determined interaction between propafenone and low dose quinidine Role of active metabolites in modulating net drug effect," Br. /. Cii . Pharmacol., 27 435-444 (1989). 

Propafenone is both a class I antidysrhythmic drug and a beta-adrenoceptor antagonist. Its pharmacological effects, clinical pharmacology, therapeutic uses, adverse effects, and interactions have been reviewed (1-5). 

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