Grapefruit and Medications

Warning labels on medications should always be taken seriously. Several medications contain a warning label that states, “Do not take with grapefruit” (or similar wording). Serious health consequences can develop if certain medications are taken with grapefruit.

How does grapefruit affect certain medications?

The U.S. Food and Drug Administration (FDA) currently lists over 50 prescription and over-the-counter medications that may negatively interact with grapefruit in the body. Grapefruit can interfere with intestinal transporters that help absorb medication, resulting in less of a medication’s active ingredients reaching the bloodstream. Grapefruit can also interfere with digestive enzymes that break down medications, resulting in the body absorbing too much of the drug.

Even small amounts of grapefruit, such as two wedges or one cup of grapefruit juice, can delay, decrease, or increase the absorption of certain medications. Seville oranges and tangelos interfere with the same enzyme as grapefruits, so they should also be avoided. Grapefruit's ability to alter the absorption of medication lasts from 1 to 3 days; therefore, eating grapefruit or drinking grapefruit juice at a different time than taking a medication that is affected by the fruit should also be avoided.

Medication warnings

Prescription medications include medication guides or information sheets that provide important safety instructions, including grapefruit interaction warnings. Over-the-counter medications have “drug facts” labels that provide a warning if grapefruit or grapefruit juice should be avoided. It is important to note that other fruit juices or drinks flavored with fruit juice should be checked to ensure grapefruit juice is not an ingredient.

Common chronic pain medications affected by grapefruit

Common chronic pain medications that can interact with grapefruit include, but are not limited to, the following:

• Alprazolam
• Carbamazepine
• Colchicine
• Fentanyl, including the fentanyl transdermal patch
• Naloxegol
• Bupropion
• Buspirone
• Diazepam
• Oxycodone

If individuals have any questions or concerns about interactions between certain medications and grapefruit, consulting a pharmacist or health care professional is recommended.