Evening primrose oil for perimenopause mood: does it work?

No trial has tested evening primrose oil specifically for mood symptoms in perimenopause. The closest evidence comes from premenstrual syndrome, and a 2021 review suggests some women may have a similar hormone-sensitivity pattern in perimenopause. There, the results don't support it. A 1996 systematic review of PMS trials concluded evening primrose oil was of little value for managing symptoms, and the two best-controlled trials in that review found no benefit over placebo. The authors noted the trials were small, so a modest effect couldn't be fully ruled out, but nothing since has changed that picture.

If you want something with stronger trial evidence for perimenopause mood specifically, perimenopause mood swing treatment covers options including SSRIs and cognitive behavioral therapy. Evening primrose oil may still be worth trying for other symptoms, but the research doesn't support a mood effect yet.

The evidence against evening primrose oil for premenstrual and perimenopausal mood symptoms is fairly consistent.

• A 1990 randomized, placebo-controlled trial of 38 women tracked PMS symptoms over six cycles. Scores improved, but so did the placebo group's, and the researchers concluded the improvement was a placebo effect, not a drug effect.
• A 1988 crossover trial of 10 women with premenstrual anxiety and low mood found no difference between evening primrose oil and placebo.
• A 2022 review of evening primrose oil research for PMS described the overall findings as contradictory, with some studies reporting improvement and others none.
• A 2024 systematic review of evening primrose oil across inflammatory conditions found some supporting evidence for menopausal hot flashes and breast pain, but listed premenstrual syndrome among the conditions where it didn't show effectiveness.

None of these trials recruited specifically perimenopausal women reporting mood symptoms, so even this evidence is indirect. For more on the mood question specifically, see evening primrose oil and mood.

If a supplement is going to help, you'd typically expect some signal within two to three menstrual cycles, which is roughly how most evening primrose oil trials for PMS were designed, running anywhere from two to six cycles total. In the 1990 trial, symptom scores dropped fastest in the first cycle, in both the treatment and placebo groups, which is part of why researchers concluded the improvement wasn't coming from the oil itself.

That timeline matters if you're deciding whether to keep taking it. If nothing's shifted after two or three cycles of daily use, a fourth cycle is unlikely to be different. For general guidance on timing across different symptoms, see how long evening primrose oil takes to work.

Evening primrose oil is generally well tolerated at typical doses. Stomach upset, nausea, loose stools and headache are the most commonly reported side effects, and they're usually mild. If a side effect doesn't ease, stop taking it.

Because gamma-linolenic acid, the active compound in evening primrose oil, has effects on inflammation and blood clotting, it's worth paying attention to any new symptoms rather than assuming they're unrelated. For the full list of reported effects, see evening primrose oil side effects.

Anyone on blood-thinning medication, anyone with a seizure disorder, and anyone who's pregnant or trying to conceive should ask first, since gamma-linolenic acid can affect clotting and may lower the seizure threshold.

If you're already taking other supplements or prescriptions for perimenopause symptoms, mention evening primrose oil to whoever manages your prescriptions so they can flag any interactions before you start. See a doctor if mood symptoms take a week or more of most months, or if you have thoughts of hurting yourself. Bring two months of daily notes so the pattern is clear from the start.

Guidelines for perimenopausal mood changes favor options with more evidence behind them than evening primrose oil. These include SSRIs, which some people take every day and others find help taking only during the days symptoms show up, along with certain hormonal treatments and cognitive behavioral therapy.

A 2021 review found that women with a history of PMDD can be more sensitive to the hormone shifts of perimenopause, which may explain why mood symptoms resurface or get worse during this transition, even in people who'd been stable for years before it. A doctor decides which of these fits your history and current symptoms. For the fuller picture on what's recommended for perimenopausal mood, read perimenopause mood changes.

Evening primrose oil won't do anything for you in the next ten minutes, and that's fine, because the moment you're in usually needs something faster. If you're mid-argument or crying and can't explain why, leave the room, set a timer for 20 minutes, and let the immediate reaction pass before you decide what to say or do next.

Writing down exactly what happened, in order, often makes it easier to see which part is the hormone shift and which part is a real problem worth addressing. Niyora is a PMS and PMDD support app. If you want somewhere to put the fight before you answer, Niyora's Moon lets you write what happened, see it from another angle and draft a reply you can hold for 20 minutes before sending it. For other ideas to try alongside supplements, see PMS supplements: what actually helps.