Drug Interaction Report

Mavacamten may reduce the blood levels and effects of medroxyPROGESTERone, which may make it less reliable as a form of birth control. Alternative or additional methods of birth control should be used during treatment with mavacamten and for 4 months after the last dose to avoid unintended pregnancy. This is particularly important because mavacamten may cause harm in the unborn child. Talk to your gynecologist or other healthcare professional for help in selecting an effective method of birth control that is best for you. If you take hormone replacement for menopause, you should contact your doctor if you experience increased frequency or worsening of your symptoms such as hot flashes, vaginal dryness, or abnormal bleeding. 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 mavacamten and increase the risk of heart failure, a condition where the heart is unable to pump blood adequately to meet the body's needs. Your risk may be further increased if you develop a serious infection or irregular heartbeat during treatment with mavacamten. You should avoid the consumption of grapefruit and grapefruit juice while taking this medication. Talk to your doctor if you have any questions or concerns. You should seek medical attention if you experience signs and symptoms of heart failure such as shortness of breath, chest pain, fatigue, swelling in your legs, palpitations, or rapid weight gain. 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.