Potential Drug Interactions

Note: The information on this site is not intended or implied to be a substitute for medical advice. Please consult your doctor or pharmacist for advice and recommendations concerning your medications and diet.

Fresh grapefruit and 100% grapefruit juice have many qualities that make them great to include as part of a healthy diet. Grapefruit contains plant compounds called furanocoumarins. These naturally occurring plant compounds may interact with the same enzymes in the body that break down certain medications and this interaction could increase the amount of medication the body absorbs, resulting in the possibility of negative or dangerous side effects.

The extent of any interaction can be different depending on the person, the drug and the amount of grapefruit consumed. For some people, consumption of one whole grapefruit or as little as 6 ounces or 177ml of 100% grapefruit juice may be enough to increase the concentration of a medication within the body which could potentially cause undesirable or unsafe outcomes.

It is important to know that:

  • While some medications may interact with grapefruit, most do not. Published studies indicate that clinically relevant interactions have only been established for a relatively small number of medications.
  • For patients who wish to continue consuming fresh grapefruit or 100% grapefruit juice and are prescribed a medication that may interact with grapefruit, their physicians often can prescribe non-interacting, alternative medications within the most commonly prescribed drug classes. These medications often can provide the same therapeutic effect with no need to avoid grapefruit.
  • It is safe to consume grapefruit while taking virtually all over-the-counter medications. Always read instructions and warnings for any medication and consult your doctor or pharmacist if you have questions or concerns.