--- title: Evening primrose oil for mood swings: what trials found description: Evening primrose oil for mood swings: trials and reviews show little benefit for anxiety or depression before your period, here's what helps instead. url: https://niyora.com/treatments/evening-primrose-oil-and-mood/ --- - [Niyora](https://niyora.com/) - [Treatments](https://niyora.com/treatments/) - Evening primrose oil for mood swings: what the trials found Treatment # Evening primrose oil for mood swings: what the trials found Evening primrose oil hasn't shown a benefit for premenstrual mood swings, anxiety or depression in the trials available: one placebo-controlled trial found no difference, and a 2024 systematic review found no effect on premenstrual syndrome overall. If your mood needs support before your period, cognitive behavioral therapy, counseling and certain medications have stronger evidence behind them. Updated 14 October 2026 Niyora editorial Limited evidence Strength of evidence Limited Only small or early studies so far. - None - Limited - Mixed - Moderate - Strong ## At a glance - No randomized trial has shown evening primrose oil works better than placebo for premenstrual depression or anxiety. - A 2024 systematic review found evening primrose oil didn't show effectiveness for premenstrual syndrome symptoms overall. - Inositol, a different supplement, showed a preliminary trend toward helping PMDD-related depressive symptoms, though not statistically significant. - Therapy-based options like CBT, mindfulness-based therapy and structured counseling have stronger trial evidence for premenstrual anxiety and depression. - See a doctor if mood symptoms take up a week of every month or involve thoughts of hurting yourself. ## Strength of evidence Limited evidence - None - Limited - Mixed - Moderate - Strong The one placebo-controlled trial on evening primrose oil for premenstrual mood symptoms found no difference from placebo, and a 2024 systematic review found no effect for premenstrual syndrome overall. Current evidence doesn't support a benefit for anxiety, depression or PMDD mood symptoms specifically. ## Can evening primrose oil cause depression or mood swings? Evening primrose oil (EPO) is a plant oil high in gamma-linolenic acid, not a hormone, so it works differently from hormonal medications. There's no trial evidence that it causes depression, anxiety, or mood swings as a side effect. People often reach for EPO because it's marketed broadly for premenstrual symptoms, including breast tenderness and bloating, not because trials have shown it helps mood specifically. The side effects most often reported are mild: - Nausea - Headache - Loose stools A 2024 systematic review of EPO across several health conditions found it didn't show effectiveness for premenstrual syndrome, but it also didn't flag new mood symptoms as a risk. If a mood change showed up after you started taking it, it's worth checking whether the timing matches your cycle rather than the supplement. [Evening primrose oil side effects](https://niyora.com/treatments/evening-primrose-oil-side-effects/) covers what else people notice, including the physical ones. ## Can evening primrose oil help anxiety or depression? The best evidence so far says no, not reliably. A small double-blind crossover trial gave women with PMS-related nervous symptoms either EPO (as Efamol and Efavit) or placebo for two months each. The trial: - Started by screening 24 women with PMS - Narrowed to 12 whose symptoms were limited to the days before their period - Had 10 women complete both treatment arms Depression and anxiety scores improved during the medication months, but they improved just as much during the placebo months. There was **no real difference** between the two. That 2024 systematic review found the same pattern more broadly. It reported no effect for premenstrual syndrome, which includes the mood symptoms that come with it. Your anxiety or low mood before your period is still real. This particular supplement just hasn't shown a measurable effect beyond what a placebo gives you in the available trial. [Evening primrose oil for PMS](https://niyora.com/treatments/evening-primrose-oil-for-pms/) walks through what the research does and doesn't support. ## Why does hormonal contraception affect mood? Hormonal contraception works differently than EPO. Instead of adding a plant oil, it changes the hormones your body makes or how steady they stay across your cycle. PMDD is a different reaction to normal hormone changes, not a result of abnormal hormone levels. That's part of why some people on hormonal contraception notice their mood settle, and others notice new mood symptoms. The same shift in hormones can land differently in different brains. This is a separate question from whether EPO helps your mood, since EPO doesn't change your hormones at all. If you're weighing hormonal contraception against a non-hormonal option like EPO, a doctor can help you match the choice to your history and symptoms. ## How long do mood side effects last? There's no established timeline here, because no trial found that EPO affects mood in either direction. The physical side effects it can cause, like nausea or a headache, are usually mild and tend to ease without needing to stop the supplement, per the 2024 systematic review of EPO across several conditions. If a mood change shows up and tracks with your cycle rather than with when you started or stopped EPO, that pattern points to hormones, not the oil. Tracking your mood alongside your cycle for a cycle or two can help you tell the difference. [Evening primrose oil dosage](https://niyora.com/treatments/evening-primrose-oil-dosage/) covers how it's typically taken. ## Can evening primrose oil help PMDD instead? The trial evidence doesn't point that way either. The one placebo-controlled trial on EPO for PMS-related nervous symptoms found no benefit over placebo, and it wasn't designed around a PMDD diagnosis specifically. The 2024 systematic review found the same lack of effect for PMS more broadly. EPO is often marketed on the idea that an imbalance in certain fatty acids contributes to premenstrual symptoms, including mood, but that idea hasn't translated into a measured benefit in the trial available. A different supplement, inositol, has shown more promise for PMDD mood symptoms specifically. A meta-analysis pooling two PMDD trials found a **trend toward inositol helping depressive symptoms**, though the result sat just short of standard significance (p = 0.07), so the evidence is still preliminary. If PMDD is what you're dealing with, [evening primrose oil for PMDD](https://niyora.com/treatments/evening-primrose-oil-for-pmdd/) covers why the condition responds differently to treatment than typical PMS, and [PMS supplements](https://niyora.com/techniques/supplements/) lays out what else has been studied. ## What are your options if your mood changes? Evening primrose oil isn't the option with the strongest evidence for premenstrual mood symptoms. A few approaches have more support behind them. | Option | What it does | Evidence strength | | --- | --- | --- | | Mindfulness-based cognitive therapy (MBCT) | Teaches skills for managing anxious or low-mood thoughts | An 8-week RCT found lower depression and anxiety scores afterward | | Group counseling or stress training | Structured sessions on managing PMS-related stress | RCTs found lower anxiety, depression and stress scores after the program | | Physical activity with positive psychology | Combines exercise with mood-focused sessions | An RCT found improved depression, anxiety and stress scores | | Psychotherapy generally | Various talk-therapy formats for PMS | A meta-analysis across seven trials found lower depression scores | | Inositol | A supplement studied specifically in PMDD | Preliminary, a trend toward benefit, not yet statistically significant | | Evening primrose oil | Plant oil taken as a supplement | No benefit over placebo in the one available trial | A doctor can also talk through: - SSRIs, which some people take only in the two weeks before their period rather than every day - Certain hormonal contraceptives Guidelines list both as options for more severe premenstrual mood symptoms, with a doctor deciding what fits. If you want somewhere to put a hard moment while you sort out what helps long term, Niyora is a PMS and PMDD support app. Its Moon feature lets you write down what happened, see it from another angle, and draft a reply you can hold onto before you send anything. When to see a doctor If premenstrual mood symptoms take up a week of every month, or you've had thoughts of hurting yourself, see a GP or gynecologist and bring two months of daily notes. From the research library ## Research on evening primrose oil 38 studies in the library look at evening primrose oil in PMS and PMDD. They were published from 1983 to 2026, and each one has a short summary of what was tested and found. 38 studies, 1983 to 2026 How strong the studies are Strong study design 4 Moderate study design 18 Early or limited evidence 16 - [Systematic review, 2009Which herbs, vitamins and minerals help treat PMS?Only calcium has good evidence to work for PMS. Chasteberry and vitamin B6 may help, but most of the 62 products people try lack proper research.Strong study design](https://niyora.com/research/papers/herbs-vitamins-and-minerals-in-the-treatment-of-premenstrual-syndrome-a-2009/) - [Systematic review, 2007What treatments work for premenstrual syndrome?Many treatments have been studied for PMS, but researchers face a major challenge: there is no standard way to measure symptom severity, making it difficult to know which treatments truly work.Strong study design](https://niyora.com/research/papers/premenstrual-syndrome-2007/) - [Study, 2002Which PMS treatments have good scientific evidence?Calcium at 1200 mg daily and certain antidepressants have good evidence of working. Many popular treatments like vitamin B6, evening primrose oil, and birth control pills lack strong evidence. Some treatments like progesterone do not work.Strong study design](https://niyora.com/research/papers/premenstrual-syndrome-evidence-based-treatment-in-family-practice-2002/) - [Randomised trial, 2000Which dietary supplements help PMS?Only calcium has strong evidence from large rigorous trials. Magnesium, vitamin E, and carbohydrate supplements show limited promise but need more research. Vitamin B6 and evening primrose oil have mixed results.Strong study design](https://niyora.com/research/papers/the-potential-for-dietary-supplements-to-reduce-premenstrual-syndrome-pms-2000/) - [Study, 2024Does a combination of evening primrose oil, tocotrienol, and vitamin B6 reduce premenstrual symptoms?Yes. In women with PMS taking this combination for 3 months, premenstrual symptoms improved significantly. The overall PMS score dropped by 61.03%, menstrual pain dropped by 75.20%, and breast tenderness dropped by 82.54%.Moderate study design](https://niyora.com/research/papers/a-real-world-study-to-evaluate-the-effectiveness-of-evening-primrose-oil-in-2024/) - [Randomised trial, 2024Does a herbal soft gel capsule with three oils reduce PMS symptoms?The capsule reduced women's PMS symptoms when compared to their baseline, but was not significantly better than taking sunflower oil.Moderate study design](https://niyora.com/research/papers/effects-of-the-herbal-soft-gel-capsule-containing-pimpinella-anisum-oenothera-2024/) [See all 38 studies on evening primrose oil](https://niyora.com/research/topics/treatment-evening-primrose/) ## Questions people ask Does evening primrose oil help anxiety? + Evening primrose oil hasn't shown a benefit for anxiety beyond placebo. A small crossover trial found anxiety scores improved equally whether women took evening primrose oil or a placebo, and a 2024 systematic review found no effect on premenstrual syndrome symptoms overall, so the current evidence doesn't support it as an anxiety treatment. Can evening primrose oil help with PMDD mood swings? + Evening primrose oil hasn't been shown to help PMDD mood swings specifically, since the available trial focused on PMS and found no benefit over placebo. Inositol, a different supplement, showed a preliminary trend toward helping PMDD-related depression in a small meta-analysis, though the result wasn't statistically significant. Can evening primrose oil cause panic attacks? + There's no trial evidence that evening primrose oil causes panic attacks or worsens anxiety. Its most commonly reported side effects are mild and physical, like nausea, headache or loose stools, rather than psychological ones. If new anxiety symptoms show up, tracking them against your cycle can help you spot the real pattern. How long does evening primrose oil take to help mood? + There's no set timeline, because trials haven't found that evening primrose oil improves mood beyond what a placebo does. If you're tracking its effect on physical symptoms instead, most people allow a couple of cycles before judging whether it's doing anything at all. What helps premenstrual mood swings if evening primrose oil doesn't? + Premenstrual mood swings have stronger evidence behind cognitive behavioral therapy, mindfulness-based therapy and structured counseling, all of which reduced anxiety and depression scores in randomized trials. A doctor can also discuss SSRIs or certain hormonal contraceptives, both recommended in treatment guidelines for more severe premenstrual mood symptoms. ## Sources - 1. [A double‐blind trial of evening primrose oil in the premenstrual syndrome: Nervous symptom subgroup](https://doi.org/10.1002/hup.470030110), Human Psychopharmacology Clinical and Experimental, 1988 - 2. [Psychotherapy for Depression and Anxiety in Premenstrual Syndrome (PMS): A Systematic Review and Meta-Analysis](https://doi.org/10.22038/ijp.2018.36729.3197), DOAJ (DOAJ: Directory of Open Access Journals), 2019 - 3. [The Effects of Mindfulness-Based Cognitive Therapy on Depression and Anxiety in Women with Premenstrual Syndrome](https://doi.org/10.1155/2016/9816481), Depression research and treatment, 2016 - 4. [A meta-analysis of inositol for depression and anxiety disorders](https://doi.org/10.1002/hup.2369), Human psychopharmacology, 2014 - 5. [The effect of Oenothera biennis (Evening primrose) oil on inflammatory diseases: a systematic review of clinical trials](https://doi.org/10.1186/s12906-024-04378-5), BMC complementary medicine and therapies, 2024 - 6. [Effectiveness of computer-based stress inoculation training (SIT) counseling approach on anxiety, depression, and stress of students with premenstrual syndrome](https://doi.org/10.1186/s12889-024-18003-0), BMC public health, 2024 - 7. [The effects of positive psychology and physical activity on depression, anxiety, and stress among students with premenstrual syndrome: a single-blind, randomized controlled trial](https://doi.org/10.1186/s12905-024-03333-3), BMC women's health, 2024 - 8. [Effect of Group Counseling on Depression, Stress, and Anxiety of Premenstrual Syndrome: A Randomized Clinical Trial](https://doi.org/10.15296/ijwhr.2022.35), International Journal of Women s Health and Reproduction Sciences, 2022 Ask AI about this page Copy prompt ChatGPT ↗ Claude ↗ Perplexity ↗ Google AI Mode ↗ Grok ↗ On this page - [Can evening primrose oil cause depression or mood swings?](#can-evening-primrose-oil-cause-depression-or-mood-swings) - [Can evening primrose oil help anxiety or depression?](#can-evening-primrose-oil-help-anxiety-or-depression) - [Why does hormonal contraception affect mood?](#why-does-hormonal-contraception-affect-mood) - [How long do mood side effects last?](#how-long-do-mood-side-effects-last) - [Can evening primrose oil help PMDD instead?](#can-evening-primrose-oil-help-pmdd-instead) - [What are your options if your mood changes?](#what-are-your-options-if-your-mood-changes) - [Research](#research) - [Questions](#faq) Niyora PMS & PMDD support For the hard moment before your period. Private, no account. [Get it on iPhone](https://apps.apple.com/app/niyora-pms-emotions/id6764561688) ## Keep reading Treatment Evening primrose oil: what it is and whether it helps PMS Treatment Evening primrose oil for PMS: does it work? Treatment Evening primrose oil for PMDD: does it work? Treatment Evening primrose oil side effects, including mood Treatment Evening primrose oil 1000 mg: dosage, timing, and benefits Treatment How long until evening primrose oil works, and what are the signs? Treatment Evening primrose oil for perimenopause mood: does it work? Treatment PMS treatment: what actually helps Condition What is PMS? Premenstrual syndrome, explained