These medicines include some medicines in the following groups: − erythromycin, ketoconazole, itraconazole, posaconazole, voriconazole, rifabutin, rifampicin, telithromycin – medicines used to treat infections − cyclosporine – a medicine used to suppress the immune system for example after organ transplantations − ritonavir, saquinavir – medicines used to treat HIV − phenytoin, carbamazepine – medicines used to treat seizures − cisapride – a medicine used to treat certain digestive system problems − pimozide – a medicine used to treat certain psychological illnesses − quinidine, digoxin – medicines used to treat certain heart problems − repaglinide – a medicine used to treat diabetes − verapamil – a medicine used to treat high blood pressure or angina − nefazodone – a medicine used to treat depression − St John’s Wort – a herb extract used to treat depression − topotecan, paclitaxel – medicines used to treat certain types of cancer − rosuvastatin – a medicine used to treat high cholesterol − drugs that decrease stomach acidity (used to treat stomach ulcers or indigestion)