Does evening primrose oil help with mood swings during perimenopause?

Evening primrose oil may offer some modest support for mood swings, though the evidence for perimenopause specifically is limited. The most relevant research comes from studies on premenstrual syndrome, where some women have found benefit. Whether those findings translate to the hormonal swings of perimenopause is not yet well established.

Evening primrose oil contains gamma-linolenic acid, or GLA. GLA converts in the body to DGLA and then to prostaglandin E1, a compound that has anti-inflammatory and mood-relevant properties. Prostaglandins interact with neurotransmitter pathways, including serotonin and dopamine signaling, which strongly influence mood regulation. The theory is that shifting the prostaglandin balance toward the anti-inflammatory E1 pathway may support more stable mood responses to hormonal changes.

During perimenopause, estrogen levels become erratic rather than simply declining. These unpredictable swings affect serotonin synthesis and the sensitivity of serotonin receptors in the brain, which can produce intense mood shifts, irritability, and episodes of low mood that feel disproportionate to circumstances. Progesterone, which has calming effects through GABA receptors, also becomes more variable. Evening primrose oil does not directly replace these hormones, but the GLA pathway may help moderate some of the downstream inflammatory signaling that amplifies mood instability.

A 1990 study by Khoo and colleagues found that evening primrose oil reduced PMS symptoms including mood-related ones compared to placebo. This is the most cited direct evidence, but PMS and perimenopause are different hormonal states. Perimenopause-specific clinical trials on evening primrose oil and mood are limited and small in scale. The honest assessment is that the evidence here is preliminary, and results vary considerably among individuals. It is also worth noting that mood swings in perimenopause often have a clear cyclical pattern in the earlier stages, worsening in the days before a period or during the luteal phase. If your worst mood episodes cluster at predictable times, that pattern itself is important information to bring to your provider, as it may point toward targeted hormonal support.

Studies on evening primrose oil for perimenopausal symptoms have generally used 3,000 to 4,000 mg per day. Splitting the dose across two meals is common practice and may reduce digestive side effects. Talk to your healthcare provider about the right dose for your situation, especially given that stronger evidence-based options for mood, including cognitive behavioral therapy, antidepressants, and hormone therapy, exist and deserve consideration.

Before starting evening primrose oil, review these safety points. If you have or have had a hormone-sensitive condition such as breast cancer, endometriosis, or uterine fibroids, discuss evening primrose oil with your healthcare provider before using it. Evening primrose oil may interact with blood thinners and anticoagulants. It may also lower the seizure threshold, so discuss with your provider if you take any seizure medications. If you take any prescription medications, check with your provider before adding this supplement.

Mood changes tend to be among the slower symptoms to respond to supplement changes. Give it at least 6 to 8 weeks before concluding it is not working, and track your mood consistently across that period rather than relying on memory. Sleep, alcohol intake, and stress levels affect mood strongly too, so addressing those alongside any supplement improves your chances of seeing a real effect. Alcohol in particular can worsen mood instability in perimenopause because it disrupts sleep and increases estrogen fluctuation, so reducing it during your trial window gives the supplement a fairer test.

See your healthcare provider if your mood swings are severe, if you are experiencing persistent low mood, hopelessness, or loss of interest lasting more than two weeks, if you are having thoughts of self-harm, or if mood disruptions are affecting your relationships or your ability to function at work. These are signs that more targeted treatment, not supplements, is the right path. Your provider can evaluate whether hormone therapy, antidepressants, or psychotherapy, or a combination of these, would be a better fit for your specific pattern. Perimenopause-related mood disruption is a real medical issue, not just something to manage on your own.

Tracking mood daily alongside cycle phase and sleep gives you and your provider real data to work with. The PeriPlan app (https://apps.apple.com/app/periplan/id6740066498) lets you log mood swings daily so you can spot whether patterns shift over time. This content is for informational purposes only and does not replace medical advice. Always consult your healthcare provider about your specific situation.