Essential Fatty Acid
Evening Primrose Oil (PMS)
Also known as: EPO, GLA, Oenothera biennis oil
GLA-rich oil traditionally used for PMS breast tenderness and hormonal symptoms.
Last reviewed June 2026 · Evidence graded from peer-reviewed research, not editorial opinion. Educational only — not medical advice.
Primary uses
- PMS breast tenderness
- Hormonal skin
- PMS symptoms
How it works
- Provides GLA
- May reduce breast tenderness
- Anti-inflammatory prostaglandins
- Traditional PMS support
Dosage
- Typical range
- 500-3000mg daily
- Timing
- With meals, divided
- With food
- Yes
- Duration
- 2-3 cycles for effect
- Special populations
- PMS, especially breast tenderness
Forms
- Softgels
- Liquid oil
Safety
Common side effects
- GI upset
- Headache
Contraindications
- Seizure disorders
- Before surgery
Evidence notes
Mixed evidence, traditionally used for PMS breast symptoms
Grade C: Mostly observational or small trials; mechanism is plausible but unproven at scale.
Related in Essential Fatty Acid
Check a full stack
Formulate's free interaction checker lets you paste in any combination of supplements and medications at once — every pairing flags severity, timing, and cited evidence.
Open the checkerWhere does Evening Primrose Oil (PMS) fit in your stack?
Answer two questions and get a stack graded on research — every ingredient scored on the evidence behind it, not the marketing.
Build my stack2 questions · free · no account needed to start
Also on iPhone — get the free app
Evidence-based supplement guides, no spam
We send a short digest when new guides drop — nothing else. No affiliate pushes, no sponsored content, unsubscribe anytime.
Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider. Individual needs and risks vary — consult a professional before starting, stopping, or combining supplements, especially if you are pregnant or nursing, taking medication, or managing a health condition.