some common pharmacological inhibitors of p-glycoprotein include: amiodarone, clarithromycin, ciclosporin, colchicine, diltiazem, erythromycin, felodipine, ketoconazole, lansoprazole, omeprazole and other proton-pump inhibitors, nifedipine, paroxetine, reserpine, saquinavir, sertraline, quinidine, tamoxifen, verapamil, and duloxetine. elacridar and cp 100356 are other common p-gp inhibitors. zosuquidar and tariquidar were also developed with this in mind. lastly, valspodar and reversan are other examples of such agents. abcb1 is linked to the daily dose of warfarin required to maintain the inr to a target of 2.5. patients with the gt or tt genotypes of the 2677g>t snp require around 20% more warfarin daily.