Drug Interaction Report

Ceritinib may increase the blood levels of sparsentan. This may increase the risk of side effects such as hepatotoxicity, acute kidney injury, hyperkalemia (high blood potassium), edema, and hypotension. Talk to your doctor if you have any questions or concerns. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment to safely use both medications. You should seek medical attention if you have fever, chills, joint pain or swelling, dizziness, fainting, confusion, shortness of breath, weak pulse or a slow or irregular heartbeat, unusual bleeding or bruising, tingling of the hands and feet, feelings of heaviness in the legs, muscle aches, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, diarrhea, abdominal pain, dark urine, pale stools, and/or yellowing of the skin or eyes, or pain or burning during urination. 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.

Do not consume grapefruit or grapefruit juice during treatment with ceritinib unless directed otherwise by your doctor. Grapefruit juice can increase the blood levels of ceritinib to dangerous levels, increasing the risk of an irregular heart rhythm that may be serious. Other, more common side effects such as diarrhea, nausea, vomiting, abdominal pain, and hyperglycemia (high blood sugar) may also increase. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with ceritinib. Food may also increase the blood levels of ceritinib. Therefore, you should take ceritinib on an empty stomach, meaning no food should be eaten for at least two hours before or after taking ceritinib. 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.

If you are taking sparsentan you should avoid potassium-containing salt substitutes or over-the-counter potassium supplements without first talking to your doctor. This can cause high levels of potassium in your blood. High levels of potassium can cause weakness, irregular heartbeat, confusion, tingling of the extremities, or feelings of heaviness in the legs. Call your doctor at once if you have any of these symptoms.

Consumption of grapefruit, grapefruit juice, and supplements that contain grapefruit should be avoided during treatment with sparsentan as they may increase the blood levels of sparsentan. This may increase the risk of side effects such as hepatotoxicity, acute kidney injury, hyperkalemia, edema, and hypotension.

Swallow sparsentan whole with water before your morning or evening meal. Take your dose with the same meal each day. Talk to your doctor 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.