Drug Interaction Report

Phenylbutazone may reduce the blood levels of abemaciclib, which may make the medication less effective in some cases. Contact your doctor if your symptoms worsen or your condition changes. Your doctor may be able to prescribe alternatives that do not interact, or you may need a dose adjustment or more frequent monitoring to safely use both medications. 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 abemaciclib. This may increase side effects such as nausea, vomiting, diarrhea, abdominal pain, decreased appetite, mouth sores, blood clots, hair loss, liver problems, and impaired bone marrow function resulting in low numbers of different types of blood cells. You may also be more likely to develop anemia, bleeding problems, or infections due to low blood cell counts. You should avoid the consumption of grapefruit and grapefruit juice during treatment with abemaciclib. Be sure to take the medication at approximately the same time everyday to maintain consistent blood levels and effects. 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.