Drug Interaction Report

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.

Interferon beta-1b may cause liver problems, and using it with other medications that can also affect the liver such as ethanol (alcohol) may increase that risk. You should avoid or limit the use of alcohol while being treated with these medications. Call your doctor immediately if you have fever, chills, joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, abdominal pain, dark urine, pale stools, and/or yellowing of the skin or eyes, as these may be signs and symptoms of liver damage. Talk to your doctor or pharmacist if you have any questions or concerns. 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.