Drug Interactions between avapritinib and etrasimod

Avapritinib should be taken on an empty stomach, one hour before or two hours after a meal. Do not consume grapefruit, grapefruit juice, or any supplements that contain grapefruit extract during treatment with avapritinib unless directed otherwise by your doctor. Grapefruit juice can increase the blood levels of avapritinib. This may increase the risk and/or severity of serious side effects such as bleeding in the brain; cognitive impairment (forgetfulness, confusion, trouble thinking); changes in mood or behavior; hallucinations; fluid retention or swelling; and decreases in blood cell counts. You may also be more likely to develop anemia, bleeding problems, or infections due to low blood cell counts. 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.

Grapefruit juice may increase the blood levels of etrasimod. You should avoid grapefruit, grapefruit juice, or any supplements that contain grapefruit extract during treatment with etrasimod unless directed otherwise by your doctor. Talk to your doctor if you have any questions or concerns. Contact your doctor if your condition changes or you experience increased side effects, such as fever, high temperature or flu-like symptoms, severe headache, confusion, seizures, dizziness, tiredness, lightheadedness, chest pain, shortness of breath, or irregular or abnormal heartbeat, blurriness or shadows in the center of your vision, and nausea, vomiting, abdominal pain, anorexia, or jaundice and/or dark 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.