Drug Interactions between nilotinib and riociguat

Do not consume grapefruit or grapefruit juice during treatment with nilotinib unless directed otherwise by your doctor. Grapefruit juice can increase the blood levels of nilotinib to dangerous levels, increasing the risk of an irregular heart rhythm that may be serious. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with nilotinib. Food may also increase the blood levels of nilotinib. Therefore, you should take nilotinib on an empty stomach, meaning no food should be eaten for at least two hours before or one hour after taking nilotinib. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Chemical substances present in cigarette smoke may reduce the blood levels of riociguat. This means that the medication may be less effective if you smoke during treatment. Let your doctor know if you are a smoker, or if you start smoking or stop smoking during treatment with riociguat, because the dosage may need to be adjusted. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Food may affect the absorption and blood levels of riociguat. To avoid significant fluctuations in blood levels of the medication, riociguat should be taken about the same time each day consistently either with or without food.