Particular caution should be used when prescribing PDE5 inhibitors for erectile dysfunction (eg, sildenafil, tadalafil, or vardenafil) for patients receiving protease inhibitors, including Reyataz. Coadministration of a protease inhibitor with a PDE5 inhibitor is expected to substantially increase the PDE5 inhibitor concentration and may result in an increase in PDE5 inhibitor-associated adverse events, including hypotension, visual changes, and priapism.