Grapefruit Juice and Prescription Drugs

Last updated: 01 August 2002

What is the problem?

Grapefruit and its juice increase the availability of certain drugs within the body that can lead to increased side effects.

What are the possible side effects?

Different people react differently, but some of the possible side effects include heart rhythm disturbances, kidney function impairment, blood pressure changes and anaemia.

Drugs that interact with grapefruit juice

Some of the drugs that interact with grapefruit or grapefruit juice are:

• Cisapride - prescribed for gastric reflux
• Cyclosporin & Tacromilmus - prescribed to prevent rejection following organ transplantation
• Felodipine - prescribed for high blood pressure
• Saquinavir - prescribed for HIV and AIDS
• Atorvastatin & Simvastatin - prescribed to lower blood cholesterol
• Amiodarone - prescribed for heart arrhythmias
• Carbamazefine - prescribed for epilepsy.

People are advised not to eat grapefruit or grapefruit juice if they are taking these medications.

What about other citrus fruits?

Sweet oranges and their juice do not cause the same reaction. However, bitter orange juice - such as that from Seville oranges - may have a similar effect to grapefruit juice.

Tangelos, which are a hybrid of grapefruit, may also interfere with medication.

What should you do?

People should carefully read the Consumer Medicine Information sheet that accompanies most prescription-only products obtainable from the pharmacist. Anyone with concerns should consult their pharmacist or doctor.