RiteMED Clarithromycin Drug Interactions

Tablet: Potentially Hazardous Interactions: Like erythromycin, concurrent use of clarithromycin with drugs metabolized by the cytochrome P-450 system may be associated with elevated serum levels of these drugs. Table 6 describes these interactions: See Tables 6a and 6b.

Click on icon to see table/diagram/image


Click on icon to see table/diagram/image

Interference with Laboratory Tests: Interactions with laboratory tests have not been established.
Suspension: Clarithromycin use in patients who are receiving theophylline may be associated with an increase of serum theophylline concentrations. Monitoring of serum theophylline concentrations should be considered for patients receiving high doses of theophylline.
Concomitant administration of single doses of Clarithromycin and Carbamazepine has been shown to result in increased plasma concentrations of Carbamazepine. Blood level monitoring of Carbamazepine may be considered.
Concomitant administration of Clarithromycin with terfenadine increases the plasma concentration of active acid metabolite of terfenadine by three-fold than that obtained with the administration of terfenadine alone. Concomitant administration of clarithromycin and oral anticoagulants may potentiate the effects of the oral anticoagulants. Prothrombin times should be carefully monitored while patients are receiving Clarithromycin and oral anticoagulants simultaneously.
Concomitant administration of single doses of Clarithromycin and ritonavir resulted in 77% increase in Clarithromycin AUC and 100% decrease in the AUC 14-OH Clarithromycin. In patient with renal impairment, dosage adjustment during concomitant administration of these drugs should be considered.
As with other macrolides, Clarithromycin has been reported to increase concentrations of HMG-CoA reductase inhibitors (eg. Lovastatin and simvastatin). Rare reports of rhabdomyolysis have been reported in patients taking these drugs concomitantly.
Simultaneous oral administration of Clanthromycin tablets and Zidovudine to HIV-infected adult patients resulted in decreased steady state, Zidovudine concentration.
There have been reports of interactions of erythromycin and/or Clarithromycin with carbamazepine, cyclosporine, tacrolimus, hexobarbital, phenytoin, alfentanil, disopyramide, lovastatin, bromocriptine, valproate, terfenadine, cisapride, pimozide, rifabutin and astemizole.