Drug Interactions between amoxicillin / clarithromycin / vonoprazan and dabigatran

Although some in vitro data indicate synergism between macrolide antibiotics and penicillins, other in vitro data indicate antagonism. When these drugs are given together, neither has predictable therapeutic efficacy. Data are available for erythromycin, although theoretically this interaction could occur with any macrolide. Except for monitoring of the effectiveness of antibiotic therapy, no special precautions appear to be necessary.

Coadministration with clarithromycin may slightly increase the bioavailability of dabigatran following oral administration of dabigatran etexilate. The proposed mechanism is clarithromycin inhibition of the P-glycoprotein efflux transporter, of which dabigatran etexilate is a substrate. When dabigatran etexilate was coadministered with clarithromycin 500 mg twice a day in healthy volunteers, increases in dabigatran peak plasma concentration (Cmax) by about 15% and systemic exposure (AUC) by about 19% were observed without any clinical safety concern. Dabigatran had no significant effect on the pharmacokinetics of clarithromycin. No dosage adjustment for dabigatran etexilate is recommended during coadministration with clarithromycin, but caution may be advisable.