Drug Interaction Report

RifAMPin can significantly reduce the blood levels of abiraterone, which may make the medication less effective in treating your condition. Using rifAMPin with abiraterone may also increase the risk of an irregular heart rhythm that may be serious and potentially life-threatening, although it is a relatively rare side effect. Talk to your doctor if you have any questions or concerns. 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.

Food can decrease the levels of rifAMPin in your body. Taking rifAMPin on an empty stomach (at least 30 minutes before or 2 hours after a meal) will make it easier for your body to absorb the medication. Avoid drinking alcohol while taking rifAMPin because alcohol use may increase the risk of damage to your liver. It is important to seek immediate medical care if you experience any severe side effects or symptoms of liver damage such as fever, chills, joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, dark colored urine, and/or yellowing of the skin or eyes. 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.

This interaction does not apply to abiraterone acetate (Yonsa) 125 mg tablets, which can be taken with or without food.

Taking abiraterone with food increases the amount of medicine that gets absorbed by the body for certain formulations. This may increase the risk of side effects such as high blood pressure, water retention, and a condition called hypokalemia (low blood potassium), which in severe cases can lead to muscle weakness, paralysis, breathing and swallowing difficulties (due to muscle paralysis), and irregular heart rhythm. You should take abiraterone once a day on an empty stomach. No food should be eaten for at least two hours before and one hour after taking abiraterone. Let your doctor know if you experience nausea, vomiting, constipation, abdominal cramping, confusion, dizziness, lightheadedness, fainting, muscle weakness, muscle cramps, numbness or tingling, rapid heartbeat, chest pain, and/or swelling in the legs or feet, as these may be symptoms of hypokalemia or excessive effects of abiraterone. 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.