Drug Interactions between Cerdelga and fedratinib

Do not consume grapefruit or grapefruit juice during treatment with eliglustat unless directed otherwise by your doctor. Grapefruit juice can increase the blood levels of eliglustat to dangerous levels. This may increase the risk of serious and potentially life-threatening cardiac side effects such as irregular heart rhythm, heart block, and cardiac arrest. Talk to your doctor if you have any questions or concerns. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, slow heart rate, weak pulse, or heart palpitations during treatment. 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.

Grapefruit juice can increase the blood levels of fedratinib. This may increase the risk of serious side effects such as Wernicke's encephalopathy, a potentially fatal condition of the brain associated with thiamine (vitamin B1) deficiency; low blood cell counts, which can lead to anemia, bleeding, and infections; severe diarrhea, nausea, and vomiting; problems in the liver or pancreas; and development of other cancers. You should avoid the consumption of grapefruit and grapefruit juice during treatment with fedratinib. You may take the medication with or without food, but taking it with a high-fat meal may help reduce nausea and vomiting. Talk to your doctor or pharmacist if you have questions on how to take this or other medications you are prescribed. 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.