Drug Interaction Report

Tazemetostat 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 medroxyPROGESTERone and for at least 6 months afterward to avoid unintended pregnancy. This is particularly important because medroxyPROGESTERone may cause fetal harm. 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.

Do not consume grapefruit or grapefruit juice during treatment with tazemetostat. Grapefruit juice can significantly increase the blood levels and effects of tazemetostat, which may increase the risk of serious side effects such as bleeding complications, pain, bone pain, tiredness, shortness of breath, excess fluid around the lungs, and development of new (second) cancers. 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.