Drug Interaction Report

Ribociclib may significantly increase the blood levels of sonidegib. This may increase side effects such as muscle spasms, muscle pain, muscle weakness, fatigue, nausea, vomiting, diarrhea, loss of appetite, weight loss, hair loss, itching, and taste abnormalities. You may also have an increased risk of developing a rare but serious condition called rhabdomyolysis that involves the breakdown of skeletal muscle tissue. In some cases, rhabdomyolysis can cause kidney damage and even death. 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 or more frequent monitoring to safely use both medications. Let your doctor know immediately if you have unexplained muscle pain, tenderness, or weakness during treatment with sonidegib, especially if these symptoms are accompanied by fever or dark colored urine. 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.

Ribociclib may increase the blood levels and effects of letrozole. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. Contact your doctor if your condition changes or you experience increased side effects. 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.

Sonidegib should be taken on an empty stomach, at least 1 hour before or 2 hours after a meal. The presence of food can significantly increase the absorption of sonidegib into the blood stream. This may increase side effects such as muscle spasms, muscle pain, muscle weakness, fatigue, nausea, vomiting, diarrhea, loss of appetite, weight loss, hair loss, itching, and taste abnormalities. You may also have an increased risk of developing a rare but serious condition called rhabdomyolysis that involves the breakdown of skeletal muscle tissue. In some cases, rhabdomyolysis can cause kidney damage and even death. Let your doctor know immediately if you have unexplained muscle pain, tenderness, or weakness during treatment with sonidegib, especially if these symptoms are accompanied by fever or dark colored urine. Grapefruit juice may also increase the blood levels of sonidegib and should be avoided. Talk to your doctor or pharmacist if you have any questions or concerns.

Patients should not consume pomegranates, pomegranate juice, grapefruit, or grapefruit juice during treatment with ribociclib unless directed otherwise by your doctor. Pomegranate juice or grapefruit juice can increase the blood levels of ribociclib. You may be more likely to experience side effects such as nausea; vomiting; diarrhea; loss of appetite; abdominal pain; mouth sores; hair loss; weakness; and impaired bone marrow function resulting in low numbers of different types of blood cells, which can increase the risk of anemia, bleeding problems, and infections. 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.