--- title: Vitex (chasteberry): uses, evidence and side effects description: Vitex (chasteberry) is an herbal supplement used for PMS. Here's what it does, what the evidence shows for mood symptoms, typical doses and side effects. url: https://niyora.com/treatments/vitex/ --- - [Niyora](https://niyora.com/) - [Treatments](https://niyora.com/treatments/) - Vitex (chasteberry): what it is and whether it helps PMS Treatment # Vitex (chasteberry): what it is and whether it helps PMS Vitex (chasteberry) is an herbal extract most consistently shown to help premenstrual breast tenderness; its effect on PMS mood symptoms is weaker and inconsistent across trials, and it hasn't been studied specifically in PMDD. There's no single proven dose, it's generally well tolerated, and a doctor's input matters if you take dopamine-related medication. Updated 13 October 2026 Niyora editorial Mixed evidence Strength of evidence Mixed Trials disagree, or the effect is small. - None - Limited - Mixed - Moderate - Strong ## At a glance - Vitex (chasteberry) is an extract from the Vitex agnus-castus shrub, traditionally used for PMS and premenstrual breast tenderness. - The clearest evidence supports vitex for breast pain before a period; evidence for PMS mood symptoms is weaker and inconsistent, and PMDD-specific research is lacking. - There's no single standardized dose. Extract strength and preparation vary by brand, and trials have used different doses. - Vitex is generally well tolerated (mild nausea, dizziness, dry mouth), though a rare case report linked it to a psychotic episode. - Vitex works through dopamine receptors, so it can interact with dopamine agonists, antipsychotics, or Parkinson's medication. ## Strength of evidence Mixed evidence - None - Limited - Mixed - Moderate - Strong Trials favor vitex for premenstrual breast tenderness. Pooled PMS symptom scores look large but studies are inconsistent, often low-quality, with signs of publication bias. Mood-symptom improvement is weaker, not clearly distinguishable from no effect, and PMDD hasn't been studied separately. ## What is vitex (chasteberry)? Vitex agnus-castus is a shrub, and its common names are chasteberry, chaste tree, and vitex. Its dried fruit, the vitex berry, has been used for centuries; monks once used it as a pepper substitute, which is where the name monk's pepper comes from (Chasteberry, American Family Physician, 2005). For roughly the last 50 years, extracts of that berry have been sold to treat premenstrual symptoms, especially breast tenderness before a period. You'll see it labeled as vitex, chasteberry, vitex agnus-castus, vitex castus, or agnus vitex. These are all names for the same plant extract, sold as capsules, tablets, or liquid tinctures. Most research uses a standardized extract rather than raw berries, and one of the most studied is a proprietary preparation called BNO 1095. That matters because results from one brand's extract don't automatically transfer to another product with a different strength or preparation. ## What does chasteberry do in the body? Scientists think vitex works mainly through dopamine. Compounds in the extract, called diterpenes, bind to D2 dopamine receptors on cells in the pituitary gland. That binding lowers release of prolactin, a hormone that spikes more than usual in some people during stress or deep sleep in the days before a period. This extra prolactin release is one known cause of premenstrual breast tenderness, or mastalgia, so dampening it is the clearest mechanism behind vitex's effect on that symptom. The same dopamine pathway may explain why vitex occasionally affects mood, including the rare side effects covered further down this page. Beyond the prolactin link, researchers haven't identified a separate, well-established mechanism for any effect of vitex on mood swings or irritability before a period. ## What is vitex used for? Vitex is used most often for premenstrual syndrome and for cyclical breast pain that shows up before a period and eases once it starts. A 2005 review in American Family Physician concluded that current evidence supports chasteberry for breast discomfort and PMS, while evidence for menstrual irregularities and fertility problems is weak. It's also marketed for very different uses, like boosting breast milk supply or lowering sex drive, but that same review found no real clinical support for either claim. If your main complaint is sore, tender breasts before your period, vitex has the most consistent trial support of any of its traditional uses. For anything else it's marketed for, treat the claim as unproven until a doctor or a specific study says otherwise. ## Does vitex help PMS or PMDD? For PMS, the trial evidence is larger than for most supplements, but it's messy. A 2017 systematic review pooled 14 randomized trials and found a large average effect compared with placebo, but the studies disagreed heavily with each other, and patterns in the data suggested that smaller, lower-quality trials were more likely to get published, which can inflate the overall average (European Psychiatry, 2017). A 2022 systematic review of 15 trials in 1,211 women found vitex reduced overall PMS symptom scores, with the biggest improvement in physical symptoms. The mood-symptom subgroup improved less, and that result wasn't clearly distinguishable from no effect (Pharmaceuticals, 2022). In plain terms, vitex's best-supported use is still physical, especially breast tenderness, rather than mood. For PMDD specifically, trials have mostly enrolled women with PMS rather than a confirmed PMDD diagnosis, so there isn't a solid evidence base yet for vitex and PMDD mood symptoms. Niyora is a PMS and PMDD support app. Its estimated PMS window can show whether your symptoms cluster in the days before your period, which is useful context before you decide whether a supplement trial makes sense. For more detail, see [vitex (chasteberry) for PMS](https://niyora.com/treatments/vitex-for-pms/), [vitex (chasteberry) for PMDD](https://niyora.com/treatments/vitex-for-pmdd/), and [vitex and mood](https://niyora.com/treatments/vitex-and-mood/). What the research says The 2017 meta-analysis found a large pooled effect (Hedge's g: -1.21) but extremely high heterogeneity between studies (I2 = 91%), plus signs of publication bias. The authors said the pooled effect should be treated as exploratory, not a settled finding (European Psychiatry, 2017). ## How much vitex should you take? There's no single agreed dose. The 2005 review in American Family Physician noted that standardization and dosing recommendations for chasteberry were still unresolved, and that hasn't changed much since. Trials have used different extracts, strengths, and schedules, including the proprietary extract BNO 1095 used in several breast-tenderness studies. Most products are taken once daily, often in the morning, but the strength per dose varies by brand, so the amount on one product's label isn't interchangeable with another's. Because of that variation, check the label of the specific product you're considering rather than assuming a standard dose exists. If you're already on other medication, ask a pharmacist about the amount before you start. For a closer look at doses used in research and on common labels, see [vitex dosage](https://niyora.com/treatments/vitex-dosage/). ## What are the side effects of vitex? Vitex is generally well tolerated. The most commonly reported side effects are mild: nausea or other stomach upset, headache, dizziness, and dry mouth. These usually don't require stopping the supplement, though you should stop taking it if any of them are severe or don't settle. Mood-related side effects are rarer, but worth knowing about. One case report described a person who developed psychotic symptoms after starting vitex for PMS, which resolved after stopping it (Archives of Clinical Psychiatry, 2019). A single case report can't tell you how often this happens, or prove vitex caused it, but it's a reason to stop taking vitex if you notice confusion, unusual thoughts, or a mood shift that feels different from your usual premenstrual pattern. For a fuller list of reported side effects, see [vitex side effects](https://niyora.com/treatments/vitex-side-effects/) and [vitex and mood](https://niyora.com/treatments/vitex-and-mood/). ## Is vitex safe with other medications? The main interaction to know about involves dopamine. Because vitex's main effect runs through dopamine receptors, the American Family Physician review advises caution if you're taking a dopamine agonist or antagonist, which includes some Parkinson's disease medications and some antipsychotics. No other herb-drug interactions were reported in that review, but that reflects limited research, not proof of safety alongside everything. If you're on hormonal birth control, an SSRI, or any other daily medication, treat that as a reason to ask a pharmacist before adding vitex, rather than a reason to avoid it outright. A doctor can also help you weigh a supplement against other options, like an SSRI used only in the days before your period or a change in hormonal contraception, depending on your specific pattern of symptoms. When to see a doctor If PMS symptoms take up a week of every month, or you're on a dopamine agonist, antipsychotic, or Parkinson's medication, see a GP or gynecologist before starting vitex and bring two months of daily notes. From the research library ## Research on vitex 89 studies in the library look at vitex in PMS and PMDD. They were published from 1997 to 2026, and each one is summarised in plain English. 89 studies, 1997 to 2026 How strong the studies are Strong study design 22 Moderate study design 25 Early or limited evidence 42 - [Randomised trial, 2023Can herbal medicine prevent or treat PMS and menstrual disorders?Yes, several herbs may help prevent PMS and menstrual disorders, but research quality is mixed and better studies are needed.Strong study design](https://niyora.com/research/papers/potensi-herbal-medicine-dalam-pencegahan-gangguan-menstruasi-dan-sindrom-2023/) - [Randomised trial, 2020What is the best dose of Vitex for treating PMS?A dose of 20 mg daily was most effective for reducing PMS symptoms. Higher dose (30 mg) was no better, and lower dose (8 mg) was less effective.Strong study design](https://niyora.com/research/papers/dose-dependent-efficacy-of-the-vitex-agnus-castus-extract-ze-440-in-patients-2020/) - [Systematic review, 2020Does Vitex agnus-castus help cyclic breast pain?Vitex appears moderately effective for reducing cyclic breast pain compared to placebo, works as well as some medications, and is safe with minimal side effects.Strong study design](https://niyora.com/research/papers/vitex-agnus-castus-for-the-treatment-of-cyclic-mastalgia-a-systematic-review-and-2020/) - [Guideline, 2019How should doctors treat PMS and PMDD?Treatment should be tailored to each woman's symptoms and life stage. Options include therapy, herbs, antidepressants, birth control to stop ovulation, and water pills.Strong study design](https://niyora.com/research/papers/interdisciplinary-consensus-on-management-of-premenstrual-disorders-in-2019/) - [Review, 2017What causes PMDD and what are the best treatments?PMDD involves an abnormal response to normal hormone changes affecting the serotonin system and brain circuits that control emotion. SSRIs are the first-line treatment, with several other options available.Strong study design](https://niyora.com/research/papers/premenstrual-dysphoric-disorder-2017/) - [Systematic review, 2017Does Vitex agnus castus help treat premenstrual syndrome?The meta-analysis found a large pooled effect of Vitex agnus castus compared to placebo, but the included studies have significant quality problems, publication bias, and very different results from each other, so we cannot confidently say it truly works.Strong study design](https://niyora.com/research/papers/the-treatment-of-premenstrual-syndrome-with-preparations-of-vitex-agnus-castus-a-2017/) ### Clinical trials - [An innovative nutraceutical formulation for appetite control and premenstrual syndrome symptom managementNo longer recruiting, Italy](https://niyora.com/research/trials/an-innovative-nutraceutical-formulation-for-appetite-control-isrctn12142665/) - [a Clinical Trial to Evaluate the Efficacy and Safety of Agnucaston Tablets in the Treatment of Premenstrual Syndrome (PMS)Completed, China](https://niyora.com/research/trials/a-clinical-trial-to-evaluate-the-efficacy-and-safety-of-nct00672607/) [See all 89 studies on vitex agnus-castus (chasteberry)](https://niyora.com/research/topics/treatment-vitex/) ## Questions people ask Does vitex help with PMDD specifically? + Vitex hasn't been well studied in women with a confirmed PMDD diagnosis. Most vitex trials enrolled women with PMS, and within those trials mood symptoms improved less consistently than physical ones like breast tenderness. If you suspect PMDD, that's a separate, more severe diagnosis worth confirming with daily tracking before trying supplements alone. How long does vitex take to work? + In the trials behind vitex's evidence, improvement in premenstrual symptoms was usually tracked over two to three menstrual cycles, not days. Breast tenderness tends to respond most reliably. If nothing has changed after a few full cycles on a consistent dose, that's a reasonable point to reassess with a doctor. Can you take vitex with hormonal birth control? + No specific interaction between vitex and hormonal birth control has been reported in the research reviewed here, but that reflects limited study, not proof of safety together. If you're on hormonal contraception, ask a pharmacist before adding vitex, especially if you're also on any other daily medication. Is chasteberry the same thing as vitex? + Yes. Chasteberry, vitex, vitex agnus-castus, chaste tree, and monk's pepper all refer to the same plant and the same extract sold as a supplement. The names are used interchangeably in product labels and in the research, though extract strength and preparation still vary by brand. What's a typical vitex dose? + There's no single standardized vitex dose. Research reviews have noted that dosing and standardization across products remain unresolved, and trials have used different extracts and strengths. Check the label of the specific product you're considering, and ask a pharmacist if you take other medication. ## Sources - 1. [The premenstrual syndrome, premenstrual mastodynia, fibrocystic mastopathy and infertility have often common roots: effects of extracts of chasteberry (Vitex agnus castus) as a solution](https://doi.org/10.1186/s40816-016-0038-z), Clinical Phytoscience, 2017 - 2. [The premenstrual syndrome, premenstrual mastodynia, fibrocystic mastopathy and infertility have often common roots. Effects of extracts of chasteberry (Vitex agnus-castus) as a solution](https://doi.org/10.18370/2309-4117.2019.45.66-74), Reproductive Endocrinology, 2019 - 3. [The treatment of premenstrual syndrome with preparations of Vitex Agnus Castus (Chaste-berry): A systematic review and meta-analysis](https://doi.org/10.1016/j.eurpsy.2017.01.1863), European Psychiatry, 2017 - 4. [Drug-induced psychotic disorder after administration of Vitex agnus castus (chasteberry) medication to treat premenstrual syndrome: a case report](https://doi.org/10.1590/0101-60830000000198), Archives of Clinical Psychiatry (São Paulo), 2019 - 5. [Chaste tree (Vitex agnus-castus)--pharmacology and clinical indications](https://doi.org/10.1078/094471103322004866), Phytomedicine : international journal of phytotherapy and phytopharmacology, 2003 - 6. [Chasteberry](https://pubmed.ncbi.nlm.nih.gov/16156340/), American family physician, 2005 - 7. [A Systematic Review and Meta-Analysis of Premenstrual Syndrome with Special Emphasis on Herbal Medicine and Nutritional Supplements](https://doi.org/10.3390/ph15111371), Pharmaceuticals (Basel, Switzerland), 2022 Ask AI about this page Copy prompt ChatGPT ↗ Claude ↗ Perplexity ↗ Google AI Mode ↗ Grok ↗ On this page - [What is vitex (chasteberry)?](#what-is-vitex-chasteberry) - [What does chasteberry do in the body?](#what-does-chasteberry-do-in-the-body) - [What is vitex used for?](#what-is-vitex-used-for) - [Does vitex help PMS or PMDD?](#does-vitex-help-pms-or-pmdd) - [How much vitex should you take?](#how-much-vitex-should-you-take) - [What are the side effects of vitex?](#what-are-the-side-effects-of-vitex) - [Is vitex safe with other medications?](#is-vitex-safe-with-other-medications) - [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 Vitex (chasteberry) for PMDD: does it work? Treatment Vitex (chasteberry) side effects, including mood changes Treatment PMS treatment: what actually helps Condition What is PMS? Premenstrual syndrome, explained Guide Magnesium, calcium, vitamin D