The short answer
The added bleeding risk from garlic supplements with sulindac is uncertain. Review the exact product, dose and your bleeding history with your prescriber.
What this answer covers
Oral garlic supplements with oral sulindac 150 or 200 mg tablets. Exact formulation, dose and duration matter; other NSAIDs and other supplement preparations are not interchangeable.
- Supplement or preparation
- Allium sativum
- Medication ingredient
- sulindac
What the evidence shows
One study of a garlic tablet product found no significant platelet aggregation change, but participants reported menstrual or nasal bleeding. The garlic phase followed an aspirin washout and excluded NSAIDs, so it did not measure this combination.
Consider this medicine’s own effects
Sulindac forms an active sulfide metabolite and an inactive sulfone metabolite. A short healthy-volunteer study found less fecal blood loss than high-dose aspirin, but the label retains serious GI warnings. That comparison does not establish long-term safety or the risk of adding a supplement.
Review the exact product
Bring the garlic product and daily amount to your pharmacist. Government guidance cautions about possible bleeding from supplements, particularly with medicines affecting bleeding. Concentrated tablets are a different exposure from garlic used in meals.
Know when to get help
oral sulindac 150 or 200 mg tablets can cause serious GI bleeding even without a supplement. Seek urgent care for vomiting blood or black, tarry stools, and report persistent stomach pain or unusual bleeding. Tell your prescriber about other pain medicines, aspirin and anticoagulants. A few hours of separation has not been shown to prevent an added bleeding effect.
Evidence and practical considerations
Side effects & toxicity
An increased bleeding or GI-injury rate specifically from garlic supplements with sulindac has not been established.
- Exact scope
- Oral garlic supplements with oral sulindac 150 or 200 mg tablets. Exact formulation, dose and duration matter; other NSAIDs and other supplement preparations are not interchangeable. with Exact sulindac IN 10237. Oral prodrug reversibly reduced to active sulfide and irreversibly oxidized to inactive sulfone. Metabolites do not replace the medication identity.
- Medication form and route
- Oral
What remains uncertain
- Available supplement-only and other-drug studies do not establish exact-pair clinical harm or exclude rare events. No validated preventive spacing interval.
Factors that may matter: Exact preparation and dose; Fasting versus fed dosing; Bleeding and ulcer history; Other medicines.
Read the supporting source summaries
Source 1: Current prescribing information
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: Prescription oral oral sulindac 150 or 200 mg tablets users; short human pharmacology studies where described.
GI and renal warnings remain despite comparatively low fecal blood loss in a short volunteer study. Hyperkalemia is reported; active sulfide and inactive sulfone have distinct roles.
How this applies: Exact current product label. Exact sulindac IN 10237. Oral prodrug reversibly reduced to active sulfide and irreversibly oxidized to inactive sulfone. Metabolites do not replace the medication identity.
Exact oral product label; no measured botanical co-use incidence. Ingredient, route, preparation and comparator differences must be retained.
Source 2: Original clinical research
pubmed.ncbi.nlm.nih.gov · Source check Sep 10, 2026
Population: 62 healthy adults aged 20-50.
No significant platelet aggregation change; menstrual and nasal bleeding were reported.
How this applies: Indirect for oral sulindac 150 or 200 mg tablets co-use; exact preparation and endpoint retained.
Open-label single product; denominators inconsistent. No simultaneous NSAID and no exact combination bleeding estimate.
Source 3: Medication terminology
rxnav.nlm.nih.gov · Source check Sep 10, 2026
Population: Terminology.
sulindac is IN.
How this applies: Exact identity.
Not clinical evidence.
Research assessment: · Open full citations ↗
Side effects & toxicity
Garlic supplements warrant review when other bleeding risks are present.
- Exact scope
- Oral garlic supplements with oral sulindac 150 or 200 mg tablets. Exact formulation, dose and duration matter; other NSAIDs and other supplement preparations are not interchangeable. with Exact sulindac IN 10237. Oral prodrug reversibly reduced to active sulfide and irreversibly oxidized to inactive sulfone. Metabolites do not replace the medication identity.
- Medication form and route
- Oral
What remains uncertain
- Precaution based on defined supplement evidence and the individual drug label; no exact combination event rate or universal discontinuation rule.
Factors that may matter: Exact preparation and dose; Fasting versus fed dosing; Bleeding and ulcer history; Other medicines.
Read the supporting source summaries
Source 1: Current prescribing information
dailymed.nlm.nih.gov · Source check Sep 10, 2026
Population: Prescription oral oral sulindac 150 or 200 mg tablets users; short human pharmacology studies where described.
GI and renal warnings remain despite comparatively low fecal blood loss in a short volunteer study. Hyperkalemia is reported; active sulfide and inactive sulfone have distinct roles.
How this applies: Exact current product label. Exact sulindac IN 10237. Oral prodrug reversibly reduced to active sulfide and irreversibly oxidized to inactive sulfone. Metabolites do not replace the medication identity.
Exact oral product label; no measured botanical co-use incidence. Ingredient, route, preparation and comparator differences must be retained.
Source 2: Government supplement guidance
nccih.nih.gov · Source check Sep 10, 2026
Population: Garlic supplement users.
Warns of possible bleeding with supplements, especially alongside medicines affecting bleeding.
How this applies: Precaution considered alongside oral sulindac 150 or 200 mg tablets labeling.
No exact NSAID-specific risk estimate or food-equivalence claim.
Research assessment: · Open full citations ↗
Review and change history
- Publication status
- Published research summary
- Clinical review
- Not yet recorded
| Date | Update |
|---|---|
| Article prepared | |
| Sources checked and article drafted. | |
| Research summary published |
Article revision: 89dce9374f9eadd3
This guide brings together the evidence records used by our interaction checker. Each finding retains its own preparation limits, research date, and source summaries.
Full citations require verification. Reading this answer and the source summaries does not.
Taking other supplements or medications?
Use the checker to explore your other combinations. Ask a pharmacist to review the exact products, amounts and medical conditions in your complete list.
Open the interaction checkerInformation, not medical advice. Do not change prescribed treatment based on this guide.