Hypersensitivity to the active substance or to any of the excipients listed in Description.
Co-administration with ketoconazole (see Interactions).
Co-administration with high-dose ritonavir (>200 mg every 12 hours) (see Interactions).
Co-administration with strong CYP3A4/5 inducers such as rifampicin, rifabutin, carbamazepine, long-acting barbiturates (e.g. phenobarbital), phenytoin and St. John's wort or with moderate CYP3A4/5 inducers such as efavirenz, nafcillin and etravirine (see Interactions).
Patients with familial short QT syndrome (see Precautions).