SYNERCID SIGNIFICANTLY INHIBITS CYTOCHROME P450 3A4 METABOLISM OF CYCLOSPORIN A, MIDAZOLAM, NIFEDIPINE AND TERFENADINE & CAUSE INCREASED PLASMA LEVELS. THEREFORE, COADMINISTRATION OF SYNERCID WITH DRUGS WHICH ARE CYTOCHROME P450 3A4 SUBSTRATES AND POSSESS A NARROW THERAPEUTIC WINDOW REQUIRES CAUTION AND MONITORING OF THESE DRUGS (E.G., CYCLOSPORINE), WHENEVER POSSIBLE.
ASTEMIZOLE, TERFENADINE, NNRTIS AND PROTEASE INHIBITORS LIKE DELAVIRDINE, NEVIRAPINE, INDINAVIR, RITONAVIR, ANTINEOPLASTIC AGENTS: VINCA ALKALOIDS (E.G., VINBLASTINE), DOCETAXEL, PACLITAXEL, BENZODIAZEPINES: MIDAZOLAM, DIAZEPAM, CALCIUM CHANNEL BLOCKERS: DIHYDROPYRIDINES (E.G., NIFEDIPINE), VERAPAMIL, DILTIAZEM, CHOLESTEROL-LOWERING AGENTS: HMG-COA REDUCTASE INHIBITORS (E.G., LOVASTATIN), GI MOTILITY AGENTS: CISAPRIDE, IMMUNOSUPPRESSIVE AGENTS: CYCLOSPORINE, TACROLIMUS, STEROIDS: METHYLPREDNISOLONE, OTHER: CARBAMAZEPINE, QUINIDINE, LIDOCAINE, DISOPYRAMIDE MAY HAVE INCREASED PLASMA CONCENTRATION ON CO-ADMINISTRATION.