Atazanavir and Tadalafil interaction

Coadministration of REYATAZ (with or without ritonavir) in patients on ADCIRCA ® : • Avoid the use of ADCIRCA ® when starting REYATAZ (with or without ritonavir).

John’s wort ( Hypericum perforatum ) Lipid-Modifying Agents: Lomitapide, lovastatin, simvastatin Phosphodiesterase-5 (PDE-5) Inhibitor Sildenafil b when dosed as REVATIO ® for the treatment of pulmonary arterial hypertension Protease Inhibitors Indinavir Non-nucleoside Reverse Transcriptase Inhibitors Nevirapine • In patients with previously demonstrated hypersensitivity…

The following dose adjustments are recommended for the use of ADCIRCA ® (tadalafil) with REYATAZ: Coadministration of ADCIRCA ® in patients on REYATAZ (with or without ritonavir): • For patients receiving REYATAZ (with or without ritonavir) for at least one week, start ADCIRCA ® at 20 mg once daily.

Use CIALIS ® (tadalafil) with caution at reduced doses of 10 mg every 72 hours with increased monitoring for adverse events.

PDE5 inhibitors: sildenafil, tadalafil, vardenafil ↑ sildenafil ↑ tadalafil ↑ vardenafil Coadministration with REYATAZ has not been studied but may result in an increase in PDE5 inhibitor-associated adverse reactions, including hypotension, syncope, visual disturbances, and priapism.

…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.