alfuzosin (Uroxatral), cisapride (Propulsid), pimozide (Orap), atorvastatin (Lipitor, Caduet), lovastatin (Mevacor, Altoprev, Advicor) or simvastatin (Zocor, Simcor, Vytorin), midazolam (Versed), triazolam (Halcion), sildenafil (Revatio) or tadalafil (Adcirca) when
used to treat pulmonary arterial hypertension, St. John's wort, rifampin (Rifadin, Rifater, Rifamate), ergonovine, ergotamine (Ergomar, Cafergot, Migergot), dihydroergotamine (D.H.E.