Drug Interaction Report

Talk to your doctor before using ritonavir together with vemurafenib. Combining these medications may decrease the blood levels of ritonavir, which may reduce its effectiveness in treating your condition. At the same time, ritonavir may cause the blood levels of vemurafenib to rise. This may increase the risk of an irregular heart rhythm that may be serious, as well as other side effects of vemurafenib. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or fast or pounding heartbeats during treatment with these medications. 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.

Vemurafenib may increase the blood levels of dasabuvir, one of the components of your hepatitis C medication. In some cases, this may increase the risk of side effects such as irregular heart rhythm and liver problems. Talk to your doctor if you have any questions or concerns. Your doctor may be able to prescribe alternatives that do not interact. You should seek immediate medical attention if you develop fever, chills, joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, dark colored urine, light colored stools, and/or yellowing of the skin or eyes, as these may be signs and symptoms of liver damage. 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.

Ritonavir should be taken with food to lessen gastrointestinal side effects. It is important that you take this medication exactly as prescribed by your doctor. Do not change your treatment or stop treatment without first talking to your doctor.

Food significantly increases the absorption of paritaprevir. You should take each dose of paritaprevir with a meal. Taking it on an empty stomach may lead to inadequate blood levels and reduced effectiveness of the medication.