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Glucosamine

Also known as: Glucosamine sulfate, Glucosamine + chondroitin

One of the best-selling joint supplements, but high-quality trials show little benefit.

Common forms: Glucosamine sulfate · Glucosamine hydrochloride · Combined with chondroitin

Draft summary, not yet reviewed by a qualified health professional · Last updated 2026-11-03

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This information is for education only and is not medical advice, diagnosis, or treatment. Supplements can interact with medications and health conditions. Check with your doctor or pharmacist before starting anything, especially if you take medication, are pregnant or breastfeeding, or have a health condition. These statements have not been evaluated by the FDA; supplements are not intended to diagnose, treat, cure, or prevent any disease.

What the evidence says

Safety

Common side effects

  • Stomach upset
  • Constipation or diarrhea

Avoid or ask your doctor first if

  • You have a shellfish allergy (some products)

Pregnancy & breastfeeding

Not enough safety data — avoid unless your provider recommends it.

Medication interactions

  • moderateBlood thinners: May increase the effect of warfarin.

This list covers common medication classes only and is not exhaustive.

Further reading