Drug Interactions between lopinavir / ritonavir and pexidartinib

Using pexidartinib together with ritonavir is not recommended. Combining these medications may significantly increase the blood levels and side effects of pexidartinib. High blood levels of pexidartinib can cause serious side effects that may affect your liver. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. Contact your doctor immediately if you experience an increase in side effects, including fever, chills, joint pain or swelling, excessive tiredness or weakness, unusual bleeding or bruising, skin rash or itching, loss of appetite, nausea, vomiting, or yellowing of the skin or the whites of your eyes. 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.

Pexidartinib may reduce the blood levels of lopinavir, which may make the medication less effective in treating HIV infection. Using pexidartinib with lopinavir may also increase the risk of an irregular heart rhythm that may be serious and potentially life-threatening, although it is a relatively rare side effect. You should seek immediate medical attention if you experience sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with these medications, whether together or alone. Contact your doctor if your condition worsens or you develop new infections during treatment with these medications. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring to safely use both 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.