Drug & supplement interaction

Fasting + Ibuprofen

Ibuprofen brand names: Motrin, Children's Motrin, Advil, Children's Advil, Fenbid Forte Gel, and others.

Moderate Interaction
The bottom line Moderate

Fasting has a moderate interaction with Ibuprofen. Fasting may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Fasting and Ibuprofen

Here is the interaction we found between these two, with the evidence behind it.

Moderate

ANTICOAGULANT/ANTIPLATELET DRUGS

Why this applies to Ibuprofen

Ibuprofen falls under ANTICOAGULANT/ANTIPLATELET DRUGS — the group Fasting interacts with.

Fasting may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Fasting has been found to increase the international normalized ratio (INR) in patients stabilized on warfarin. Closely monitor patients who are fasting while taking anticoagulant or antiplatelet drugs. Dose adjustment may be necessary.
Severity Moderate Likelihood Possible Evidence D

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.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the situation with ibuprofen and fasting. Ibuprofen is an NSAID, and even on its own it can irritate the stomach lining and nudge up your risk of bleeding or ulcers. Going without food adds two things to watch: an empty stomach can make ibuprofen harder on your gut, and there's some anecdotal evidence that fasting itself may slightly raise bleeding risk in people on blood thinners.

To be clear, this is weak evidence (mostly anecdotal), so I don't want to alarm you. But it's smart to take ibuprofen with a little food or a full glass of water when you can, and watch for stomach pain, black or tarry stools, or unusual bruising. If you fast regularly or use ibuprofen often, please check in with your pharmacist or doctor first.

References
  1. Wilhelmi de Toledo F, Grundler F, Bergouignan A, Drinda S, Michalsen A. Safety, health improvement and well-being during a 4 to 21-day fasting period in an observational study including 1422 subjects. PLoS One. 2019;14(1):e0209353. PubMed
  2. Katada Y, Nakagawa S, Nishimura A, et al. Effects of fasting on warfarin sensitivity index in patients undergoing cardiovascular surgery. Eur J Clin Pharmacol. 2019;75(4):561-568. PubMed
  3. Lai YF, Cheen MHH, Lim SH, et al. The effects of fasting in Muslim patients taking warfarin. J Thromb Haemost. 2014;12(3):349-54. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction 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.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Fasting Also Interacts With Other Medications

Fasting has 2 major, 205 moderate known drug interactions in our database — the Ibuprofen one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Fasting

Covers the 2,830 medications we’ve checked against Fasting. Pick one to open its full report.

From our Q&A

Questions About Fasting or Ibuprofen

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Fasting or Ibuprofen, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Ibuprofen

This page covers Fasting only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Ibuprofen page lists 286 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Asarabacca (major), Beer (major), Danshen (major) and Piracetam (major).

By severity: 7 major · 243 moderate · 36 minor.

From our pharmacist’s overview on the Ibuprofen page

“Most people treat ibuprofen (Advil, Motrin) as an everyday pain reliever, which is exactly why this list of 286 interacting supplements deserves real attention rather than a shrug. The dominant pattern by far is bleeding: 202 of these ingredients can add to the bleeding and stomach irritation ibuprofen already causes, and the seven maj…”

Reviewed by 2 · Jul 18, 2026

Open the Ibuprofen interaction page

How much people look this up

Where Fasting and Ibuprofen Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Fasting
Top half

#697 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Ibuprofen
Top 1%

#19 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Eating pattern

About Fasting

What is Fasting?

  • Weight loss
  • Blood sugar control
  • Heart health
  • Religious or spiritual practice
  • General wellness and longevity

Fasting means voluntarily going without food (and sometimes drink) for set periods. Some research suggests it may help with weight loss and blood sugar in certain people, but results vary and quality of evidence is mixed. It is not safe for everyone, so check with your doctor or pharmacist before starting—especially if you take medication or have a health condition.

Read the full Fasting monograph & all interactions
Medication

About Ibuprofen

What Is Ibuprofen Used For?

Brand names: Motrin, Children's Motrin, Advil, Children's Advil, Fenbid Forte Gel, Ibugel Forte, Arthrofen, Ebufac, Rimafen, Calprofen, Fenpaed, Galprofen, Nurofen for Children, Orbifen for Children, Brufen, Brufen Retard, Fenbid, Tab-Profen, Ibuprofen, Calodor

Oral ibuprofen products (tablets, coated tablets, and liquid-filled capsules) are used to temporarily relieve minor aches and pains from headache, backache, toothache, muscular aches, menstrual cramps, minor arthritis pain, and the common cold, and to temporarily reduce fever. The oral prescription tablet (Ibu) is also indicated for the signs and symptoms of rheumatoid arthritis and osteoarthritis, mild to moderate pain, and primary dysmenorrhea (painful periods).

Caldolor, an intravenous (IV) form, is approved for adults and children 3 months and older to manage mild to moderate pain, to manage moderate to severe pain alongside opioid pain medicines, and to reduce fever. A separate intravenous solution, Ibuprofen Lysine, is used specifically in premature infants to close a patent ductus arteriosus (PDA) — an abnormal blood vessel connection near the heart — when standard medical management has not worked.

See full Ibuprofen drug information
Keep checking

Other Drugs & Fasting

Browse every other medication we’ve checked against Fasting — both the ones with a known interaction and the ones without. Select any drug for the full detail.

2Major
205Moderate
0Minor
2,622No known interaction
Major

2 interactions

Moderate

205 interactions

Showing 60 of 205 moderate interactions — see all 205 on the Fasting page.

No interaction 2,622 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

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

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Pharmacist Counseling Corner

Following Fasting While Taking Ibuprofen: Common Questions

Can you follow Fasting while taking Ibuprofen?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Fasting and Ibuprofen interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.