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ingestible · for pms & menstrual health

Omega-3 Fatty Acids (Fish Oil)

Reviewed by the Nimbera editorial team · Last updated May 2026

Rahbar et al. 2012 Int J Gynaecol Obstet (PMID 22261128) - Double-blind crossover RCT found omega-3 supplementation for 3 months significantly reduced menstrual pain intensity (p < 0.05) and reduced ibuprofen rescue doses from 5.3-6.0 tablets (placebo) to 3.2-4.3 tablets (omega-3; p=0.001).$20-45 per month

How to use

Take 1000-2000 mg of combined EPA + DHA per day from fish oil capsules. Look for a product providing at least 180 mg EPA and 120 mg DHA per 1000 mg capsule. Take with food to improve absorption and reduce fishy aftertaste. Allow 2-3 full menstrual cycles to see maximum benefit as omega-3 incorporation into cell membranes takes time.

How it works

Prostaglandin E2 and F2-alpha cause uterine muscle contractions and ischemia that produce dysmenorrhea. Omega-3 fatty acids (EPA and DHA) compete with arachidonic acid in the prostaglandin synthesis pathway, shifting production toward less inflammatory prostaglandins (series 3) and reducing uterine cramping. EPA is also a precursor to anti-inflammatory resolvins and protectins.

Where to buy

Nordic Naturals Ultimate Omega ($35-$45/60 softgels), Carlson Labs Fish Oil ($20-$30/100 softgels), Thorne Super EPA ($38-$48/90 caps). Choose brands with third-party testing for heavy metals (IFOS certified). Available at Whole Foods, Costco, Vitamin Shoppe, Amazon.

Typical cost: $20-45 per month

Safety notes

Fish oil has blood-thinning properties - inform your doctor if you take anticoagulants (warfarin, aspirin, clopidogrel) or have a bleeding disorder or upcoming surgery. High doses (over 3 g/day) may raise LDL cholesterol in some individuals. May cause fishy burps, loose stools, or nausea - take with food and refrigerate to reduce oxidation. Choose molecularly distilled or third-party tested products to minimize heavy metal exposure. Those with fish or shellfish allergies should use algal DHA instead.

Drug & supplement interactions

  • Always tell your doctor or pharmacist about any supplements you take.
  • Interactions can occur with prescription medications, blood thinners, and immunosuppressants.
  • Herbal remedies can affect how the body absorbs or metabolises drugs.
  • Check drugs.com interactions checker before starting.

Clinical source

Rahbar et al. 2012 - Int J Gynaecol Obstet (PMID 22261128)

This information is compiled from primary clinical literature and is for informational purposes only. It is not a substitute for professional medical advice. Read our full disclaimer.