There are multiple interactions reported between these two agents.

Interaction Details

Naproxen is classified as belonging to the following category: Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, grapefruit juice might increase levels of drugs metabolized by CYP1A2.
In vitro research suggests that grapefruit juice might inhibit CYP1A2 enzymes. So far, this interaction has not been reported in humans.

Interaction Rating

Moderate

Likelihood of Occurrence

Possible

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists

References

  • Unger M, Frank A. Simultaneous determination of the inhibitory potency of herbal extracts on the activity of six major cytochrome P450 enzymes using liquid chromatography/mass spectrometry and automated online extraction. Rapid Commun Mass Spectrom 2004;1

Interaction Details

Naproxen is classified as belonging to the following category: Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, grapefruit juice might increase levels of drugs metabolized by CYP2C9.
In vitro research suggests that grapefruit juice might inhibit CYP2C9 enzymes. So far, this interaction has not been reported in humans.

Interaction Rating

Moderate

Likelihood of Occurrence

Possible

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists

References

  • Unger M, Frank A. Simultaneous determination of the inhibitory potency of herbal extracts on the activity of six major cytochrome P450 enzymes using liquid chromatography/mass spectrometry and automated online extraction. Rapid Commun Mass Spectrom 2004;1

Grapefruit Overview

Grapefruit Grapefruit is a tropical citrus fruit known for its tart and tangy flavor. They are a good source of vitamin C and other nutrients, including vitamin A, potassium, and fiber. There are several varieties of grapefruits, including white, pink, and red. This color difference is mostly attributed to their respective lycopene content. White grapefruits are the most common and have a slightly bitter taste. Pink and red grapefruits are sweeter and have a more complex flavor. Grapefruit and grapefruit seed extract is commonly used in dietary supplements for a variety of conditions, such as yeast infections, urinary tract infections, and respiratory infections. It is also sometimes used to treat digestive problems, such as diarrhea and indigestion. Drug interactions with grapefruit are quite prevalent and if you take prescription medication, you should talk with your doctor or pharmacist first before consuming grapefruit.
See More Information Regarding Grapefruit

Naproxen Overview

  • Prescription naproxen is used to relieve pain, tenderness, swelling, and stiffness caused by osteoarthritis (arthritis caused by a breakdown of the lining of the joints), rheumatoid arthritis (arthritis caused by swelling of the lining of the joints), juvenile arthritis (a form of joint disease in children), and ankylosing spondylitis (arthritis that mainly affects the spine). Prescription naproxen tablets, extended-release tablets, and suspension are also used to relieve shoulder pain caused by bursitis (inflammation of a fluid-filled sac in the shoulder joint), tendinitis (inflammation of the tissue that connects muscle to bone), gouty arthritis (attacks of joint pain caused by a build-up of certain substances in the joints), and pain from other causes, including menstrual pain (pain that happens before or during a menstrual period). Nonprescription naproxen is used to reduce fever and to relieve mild pain from headaches, muscle aches, arthritis, menstrual periods, the common cold, toothaches, and backaches. Naproxen is in a class of medications called NSAIDs. It works by stopping the body's production of a substance that causes pain, fever, and inflammation.

See More Information Regarding Naproxen

Grapefruit - More Interactions

Grapefruit interacts with 945 drugs

Interaction Rating Key

These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.

Major The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur.
Moderate Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur.
Minor Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction.
Unknown No interactions have been reported or no interaction data is currently available.

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Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Drug descriptions are provided by MedlinePlus.

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In addition to being a clinical pharmacist specializing in pharmacotherapy, Dr. Brian Staiger is a registered herbalist through the American Herbalist Guild. He has combined his passion for pharmacy practice with the study of medical ethnobotany to improve patient care. Feel free to reach out about any of your herbal or medication questions!

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