Drug Interactions between Phenytoin Sodium, Extended Release and revumenib

Phenytoin levels may decrease when the suspension is given with enteral feedings. This could lead to a loss of seizure control. You could interrupt the feeding for 2 hours before and after the phenytoin dose. Alternatively, you may give the phenytoin suspension diluted in water and flush the tube with water after administration. These would make it easier for your body to absorb the medication. However, this still may not entirely avoid the interaction and may not always be feasible. You should have your phenytoin levels checked upon starting and stopping of enteral feedings. In addition, using phenytoin together with food may alter the effects of phenytoin. Contact your doctor if you experience worsening of seizure control or symptoms of toxicity, including twitching eye movements, slurred speech, loss of balance, tremor, muscle stiffness or weakness, nausea, vomiting, feeling light-headed, fainting, and slow or shallow breathing. If your doctor does prescribe these medications together, you may need a dose adjustment or special test to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Ask your doctor before making any changes to your therapy.

High fat content meals may affect the absorption of revumenib. It is recommended that revumenib be taken while fasting or with a low fat meal (approximately 400 calories, with 25% of calories from fat). Grapefruit juice may also increase the blood levels of revumenib which can increase the risk of an irregular heart rhythm that may be serious and potentially life-threatening. You may be more susceptible if you have a heart condition called congenital long QT syndrome, other cardiac diseases, conduction abnormalities, or electrolyte disturbances (for example, magnesium or potassium loss due to severe or prolonged diarrhea or vomiting). Increased levels of [CS1] may also increase the risk of developing a serious and potentially life-threatening condition called differentiation syndrome. Symptoms of differentiation syndrome include: fever, cough, shortness of breath, severe headache, confusion, dizziness, rapid weight gain, swelling, or decreased urination. You should seek immediate medical attention if you develop any of these symptoms and/or symptoms of QT prolongation such as sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with revumenib. The risk and/or severity of other side effects may also increase, including nausea, vomiting, diarrhea, fever or infections. You may need additional monitoring if grapefruit or grapefruit juice are consumed during treatment with revumenib. Talk to a healthcare provider 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.