Clarithromycin and Tadalafil interaction

Co-administration of these phosphodiesterase inhibitors with clarithromycin is not recommended.

Phosphodiesterase inhibitors: Sildenafil Tadalafil Vardenafil Use With Caution Sildenafil, Tadalafil, Vardenafil: Each of these phosphodiesterase inhibitors is primarily metabolized by CYP3A, and CYP3A will be inhibited by concomitant administration of clarithromycin.

Co-administration of clarithromycin with sildenafil, tadalafil, or vardenafil will result in increased exposure of these phosphodiesterase inhibitors.

Increased systemic exposure of these drugs may occur with clarithromycin; reduction of dosage for phosphodiesterase inhibitors should be considered (see their respective prescribing information).

…Physicians should be aware that CIALIS for once daily use provides continuous plasma tadalafil levels and should consider this when evaluating the potential for interactions with medications (e.g., nitrates, alpha-blockers, anti-hypertensives and potent inhibitors of CYP3A4) and with substantial consumption of alcohol [see Drug Interactions ( 7.1 , 7.2 , 7.3 )] .

The dose of CIALIS for use as needed should be limited to 10 mg no more than once every 72 hours in patients taking potent inhibitors of CYP3A4 such as ritonavir, ketoconazole, and itraconazole [see Drug Interactions ( 7.2 )] .

In patients taking potent inhibitors of CYP3A4 and CIALIS for once daily use, the maximum recommended dose is 2.5 mg [see Dosage and Administration ( 2.7 )] .

CYP3A4 inhibitors (e.g. ketoconazole, ritonavir) increase CIALIS exposure ( 2.7 , 5.10 , 7.2 ) requiring dose adjustment: CIALIS for use as needed: no more than 10 mg every 72 hours CIALIS for once daily use: dose not to exceed 2.5 mg CYP3A4 inducers (e.g. rifampin) decrease CIALIS exposure ( 7.2 ).

Studies have shown that drugs that inhibit CYP3A4 can increase tadalafil exposure.