Drug Interactions between Akeega and tolvaptan

You should avoid drinking grapefruit juice during treatment with tolvaptan. Grapefruit juice can cause too much of the medication to be in the blood. Serious nervous system side effects such as difficulty swallowing, trouble speaking, muscle weakness, trouble controlling body movements, confusion, mood changes, seizures, and coma may occur. 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.