Does vitamin B6 help with PMS and menopause symptoms?

For PMS, possibly a little, on old and weak evidence. The only pooled analysis, from 1999, covered 9 placebo-controlled trials in 940 women and found vitamin B6 raised the odds of overall improvement, with an odds ratio of 2.32 (95% CI 1.95 to 2.54). The authors called most of the trials low quality, and only one of the nine was big enough. For menopause, we found no trial of vitamin B6 alone with menopausal symptoms as its main outcome.

Unsettled. Every review since 1999 lands on the word may. The 1999 authors judged doses up to 100 mg a day likely to help. A 2009 review found good-quality support only for calcium and said vitamin B6 may be effective. A 2025 review of 31 randomized trials in 3,254 women found B6 consistently eased the psychological symptoms, without pooling the numbers, and only 1 of its 31 trials was at low risk of bias. Nobody has run the large modern placebo trial that would settle it.

What the trials found

The pooled review

In the 1999 systematic review, 4 trials in 541 women reported premenstrual depression, and the odds of improvement on vitamin B6 were 1.69 times those on placebo (95% CI 1.39 to 2.06). These are odds, which run larger than risks, and the abstract gives no absolute count. All trials except one had statistical power below 70%, so most were too small to find a medium effect reliably. The review found no link between dose and benefit. Higher doses did not work better, and the authors saw no reason to go above 100 mg a day.

Single trials

The trials point in different directions, which is what small trials with different doses and scales tend to do.

In a UK general practice crossover trial, 63 women took 50 mg a day for 3 months. Only 32 completed it, and among them B6 helped emotional symptoms such as depression, irritability and tiredness, and nothing else. In another general practice trial of 617 women, 7 of 9 single symptoms improved equally on B6 and on placebo, while the overall assessment after three cycles favored B6 (p less than 0.02). Its abstract does not give the dose.

In 55 women with moderate to severe premenstrual mood changes, 150 mg a day for 2 months helped some behavioral symptoms and left much of the physical and mood picture in place. In 120 women with severe PMS, 300 mg a day cut symptoms by 45.3%, which sat inside the 39.4% to 46.1% seen on placebo. Fluoxetine at 10 mg in the same trial cut them by 65.4%.

In a 2020 New Zealand trial of 78 women, 80 mg a day for three cycles gave medium-sized drops in symptoms (effect sizes 0.43 to 0.56), with 60% in full remission against 72% on a broad micronutrient formula. There was no placebo group, so the placebo effect cannot be separated out. The US Office of Dietary Supplements cites a trial of 94 women in which 80 mg a day for three cycles reduced many PMS symptoms, especially anxiety. We could not find an abstract for that trial anywhere.

With magnesium

In a crossover trial of 44 women with mild premenstrual symptoms, 200 mg of magnesium with 50 mg of vitamin B6 for one cycle eased anxiety-related symptoms (p = 0.040), while the overall analysis showed no difference between the individual treatments. A 2017 review that leaned mostly on that trial concluded that the pair reduced premenstrual anxiety and that either one alone had no effect.

Menopause

The evidence here is close to empty. In a 6-month trial in India of 180 postmenopausal women with mild cognitive impairment, 25 mg of pyridoxine a day did not significantly change overall menopause quality of life (p = 0.3724). Menopause symptoms were a secondary outcome and there was no placebo. In a cross-sectional study of 262 Japanese women aged 40 to 65, those eating more vitamin B6 had milder hot flushes, with an odds ratio of 0.92 (95% CI 0.86 to 0.97) per 10 mcg/MJ of intake. That is an association at one point in time and cannot show that B6 causes the difference.

Who should be careful

The safety question with vitamin B6 is nerve damage, and it is real. The US Office of Dietary Supplements says 1 to 6 g of pyridoxine a day for 12 to 40 months can cause severe and progressive sensory nerve damage with loss of control of movement. The PMS trials used lower doses, 50 to 300 mg a day, and lower is not the same as safe. In the 1999 review only 1 of the 940 women reported symptoms that could fit pyridoxine nerve damage, and the authors note nerves were not formally examined, so early damage could have been missed. The authors of the 150 mg trial called for caution because of reports of toxic effects at low doses.

Not for everyone. The upper limits disagree sharply. In the United States the limit for adults is 100 mg a day, set by halving the dose used in the studies of long-term harm. In 2023 the European Food Safety Authority set 12 mg a day for adults, including pregnant and breastfeeding women. Most doses tested for PMS, 50 to 100 mg a day and more, sit above the European limit. If you take the anti-seizure drugs phenytoin or phenobarbital, 200 mg a day of pyridoxine for 12 to 120 days can lower their blood levels, so high-dose B6 is a decision to make with the person treating you.

What expert bodies say

The US Office of Dietary Supplements says some evidence suggests vitamin B6 supplements could reduce PMS symptoms, and that conclusions are limited by the poor quality of most studies. On safety, the US and European limits above are the two official positions, and they are far apart. We could not read the 2023 guideline of the American College of Obstetricians and Gynecologists, whose abstract does not mention B6, or the UK NICE clinical summary on PMS.

How we searched

What would change this answer

• A modern, properly sized placebo-controlled trial of vitamin B6 at or below 50 mg a day, with a standard daily symptom diary and nerve checks. The pooled evidence is older than many of the women who would read this page.
• A new meta-analysis with a pooled B6 estimate. None has been published since 1999.
• Any randomized trial of vitamin B6 alone for hot flushes or other menopause symptoms. We found none, and none registered.
• An agreement between the US and European upper limits. While one says 100 mg and the other 12 mg, most of the doses tested for PMS are safe by one standard and too high by the other.

More on the vitamin itself: vitamin B6.

Sources

1. ev-b6pms-01 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized placebo-controlled trials · n = 940
   Odds ratio relative to placebo for an improvement in overall premenstrual symptoms was 2.32 (95% confidence interval 1.95 to 2.54).
   
   Who: women with premenstrual syndrome in 9 published randomized placebo-controlled trials
   Effect: overall premenstrual symptoms improved: OR 2.32 (95% CI 1.95 to 2.54) versus placebo
   Certainty: Authors: conclusions are limited by the low quality of most RCTs; OR is odds, not risk.
   BMJ, 1999 · checked 2026-10-07 · we read the abstract
2. ev-b6pms-02 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized placebo-controlled trials · n = 541
   Odds ratio relative to placebo for an improvement in depressive symptoms was 1.69 (1.39 to 2.06) from four trials representing 541 patients.
   
   Who: women with premenstrual syndrome in 4 randomized placebo-controlled trials reporting depressive symptoms
   Effect: premenstrual depressive symptoms improved: OR 1.69 (95% CI 1.39 to 2.06) versus placebo
   Certainty: Secondary analysis; the same quality limitations.
   BMJ, 1999 · checked 2026-10-07 · we read the abstract
3. ev-b6pms-03 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized placebo-controlled trials · n = 940
   Results suggest that doses of vitamin B-6 up to 100 mg/day are likely to be of benefit in treating premenstrual symptoms and premenstrual depression.
   
   Who: women with premenstrual syndrome in 9 trials
   Effect: benefit likely at doses up to 100 mg/day; conclusions limited by trial quality
   Certainty: No synthesis newer than 1999 with a pooled effect estimate for B6 specifically was found.
   BMJ, 1999 · checked 2026-10-07 · we read the abstract
4. ev-b6pms-04 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized placebo-controlled trials · n = 9 trials
   Only one of the nine studies included a sufficient number of patients, and all the other trials had low statistical power (<70%).
   
   Who: 9 randomized placebo-controlled trials of vitamin B6 for PMS
   Effect: 1 of 9 trials adequately powered (about 65 per arm needed for a medium effect); 8 of 9 below 70% power
   Certainty: A methodological limitation of the whole body of evidence, not a separate effect.
   BMJ, 1999 · checked 2026-10-07 · we read the fulltext
5. ev-b6pms-05 · Meta-analysis or systematic review · dose-response analysis within a systematic review of RCTs · n = 940
   There was no correlation between the amount of vitamin B-6 given and its efficacy.
   
   Who: 9 randomized trials using vitamin B6 alone or in multivitamin preparations
   Effect: no correlation between dose and efficacy; authors see no rationale for more than 100 mg/day
   Certainty: An argument against high doses: there is no more benefit, and the risk of neuropathy rises.
   BMJ, 1999 · checked 2026-10-07 · we read the fulltext
6. ev-b6pms-06 · Meta-analysis or systematic review · adverse-event summary within a systematic review of RCTs · n = 940
   Only one patient of the 940 participating in these trials indicated the presence of any side effects that could be attributed to the neuropathy associated with pyridoxine toxicity.
   
   Who: 940 women with PMS in 9 randomized trials of vitamin B6
   Effect: 1 of 940 participants reported symptoms possibly due to pyridoxine neuropathy
   Certainty: The authors caution: without a neurological examination, early nerve damage could have been missed.
   BMJ, 1999 · checked 2026-10-07 · we read the fulltext
7. ev-b6pms-07 · Meta-analysis or systematic review · systematic review of RCTs with Cochrane RoB 2, narrative synthesis · n = 3254
   Treatment with vitamin B6, calcium, and zinc consistently had significant positive effects on the psychological symptoms of PMS.
   
   Who: women of reproductive age, 15 to 50 years, in 31 RCTs of nutritional interventions for PMS
   Effect: vitamin B6 consistently improved psychological PMS symptoms; narrative synthesis, no pooled estimate; 1 of 31 trials at low risk of bias
   Certainty: No meta-analysis; most RCTs have a high risk of bias.
   Nutr Rev, 2025 · checked 2026-10-07 · we read the abstract
8. ev-b6pms-08 · Meta-analysis or systematic review · systematic review of RCTs · n = —
   Data supports the use of calcium for PMS, and suggests that chasteberry and vitamin B6 may be effective.
   
   Who: randomized trials of natural products for PMS or PMDD, searched to April 2008
   Effect: calcium: supported; vitamin B6 and chasteberry: may be effective; meta-analysis not possible
   Certainty: Heterogeneity of doses and scales did not allow pooling the data.
   Can J Clin Pharmacol, 2009 · checked 2026-10-07 · we read the abstract
9. ev-b6pms-09 · Meta-analysis or systematic review · systematic review of randomized and pseudo-randomized trials, narrative synthesis · n = 14 studies
   Combined magnesium and vitamin B6 supplementation reduced premenstrual anxiety but had no effect when used in isolation and did not affect stress in women suffering from dysmenorrhea when combined or used in isolation.
   
   Who: women 18 years and over in randomized and pseudo-randomized supplement trials; 14 studies
   Effect: Mg plus B6: premenstrual anxiety reduced; Mg or B6 alone: no effect; no effect on stress in dysmenorrhoea
   Certainty: The conclusion on Mg+B6 rests mainly on one small RCT (44 women, 1 cycle).
   JBI Database System Rev Implement Rep, 2017 · checked 2026-10-07 · we read the abstract
10. ev-b6pms-10 · Randomized controlled trial(s) · randomized double-blind placebo-controlled crossover trial · n = 63
    In these women a significant beneficial effect (P less than 0.05) of pyridoxine was observed on emotional type symptoms (depression, irritability and tiredness).
    
    Who: women aged 18 to 49 with moderate to severe premenstrual symptoms from UK general practice
    Effect: 50 mg/day for 3 months: significant benefit (P < 0.05) on depression, irritability and tiredness; no effect on other symptom types
    Certainty: Only 32 of 63 completed.
    J R Coll Gen Pract, 1989 · checked 2026-10-07 · we read the abstract
11. ev-b6pms-11 · Randomized controlled trial(s) · randomized blinded placebo-controlled trial · n = 617
    However, improvement as measured by global assessment after three cycles was significantly greater in the patients treated with pyridoxine (p less than 0.02).
    
    Who: women with premenstrual symptoms diagnosed by their GP
    Effect: 7 of 9 symptoms improved in both arms, no significant difference; global assessment better with pyridoxine (p < 0.02)
    Certainty: The dose is not stated in the abstract; no full text.
    J Int Med Res, 1985 · checked 2026-10-07 · we read the abstract
12. ev-b6pms-12 · Randomized controlled trial(s) · randomized double-blind placebo-controlled trial · n = 120
    Fluoxetine in 10-mg doses obtained a mean reduction of 65.4% in symptoms, followed by propanolol (58.7%), alprazolam (55.6%), pyridoxine (45.3%) and placebo (39.4-46.1%).
    
    Who: women with severe premenstrual syndrome, 30 per drug group, 3 months placebo and 3 months active
    Effect: pyridoxine 300 mg/day: 45.3% symptom reduction; placebo 39.4-46.1%; fluoxetine 10 mg 65.4%
    Certainty: The dose of 300 mg is higher than the US UL (100 mg) and the EU UL (12 mg), with no advantage over placebo.
    Int J Gynaecol Obstet, 1998 · checked 2026-10-07 · we read the abstract
13. ev-b6pms-13 · Randomized controlled trial(s) · randomized double-blind treatment-controlled pilot trial, no placebo arm · n = 78
    Linear-mixed model analyses indicated both treatments produced comparable reduction in PMS symptoms with medium effect sizes (ES) across all PMS variables as measured by the DRSP (micronutrient ES = 0.50-0.56; B6 ES = 0.43-0.56), with 72% of the micronutrient and 60% of the vitamin B6 group identified as in full remission in PMS symptoms after three cycles.
    
    Who: regularly menstruating women with PMS, New Zealand; 72 of 78 completed
    Effect: B6 effect sizes 0.43-0.56 on DRSP; full remission 60% (B6) vs 72% (micronutrients); no serious adverse effects
    Certainty: No placebo: the placebo effect is not separated out.
    J Altern Complement Med, 2020 · checked 2026-10-07 · we read the abstract
14. ev-b6pms-14 · Randomized controlled trial(s) · randomized double-blind placebo-controlled crossover trial, Latin square · n = 44
    ANOVA showed no overall difference between individual treatments, but predefined treatment comparisons using factorial contrasts in ANOVA showed a significant effect of 200 mg/day Mg + 50 mg/day vitamin B6 on reducing anxiety-related premenstrual symptoms (nervous tension, mood swings, irritability, or anxiety) (p = 0.040).
    
    Who: women with mild premenstrual symptoms, average age 32
    Effect: Mg + B6 reduced anxiety-related symptoms (p = 0.040); no overall difference between individual treatments
    Certainty: One cycle per treatment; the authors call the effect modest.
    J Womens Health Gend Based Med, 2000 · checked 2026-10-07 · we read the abstract
15. ev-b6pms-15 · Randomized controlled trial(s) · randomized double-blind placebo-controlled trial · n = 55
    In light of recently reported, potentially toxic effects of low doses of vitamin B6, our results call for caution in using this therapy for premenstrual symptoms.
    
    Who: women with moderate to severe premenstrual mood changes
    Effect: 150 mg/day: improvement in autonomic and behavioral symptoms; much physical and affective symptomatology remained
    Certainty: The authors explicitly refer to reports of toxicity at low doses.
    Obstet Gynecol, 1987 · checked 2026-10-07 · we read the abstract
16. ev-b6pms-16 · Position of an expert body · agency fact sheet · n = —
    Some evidence suggests that vitamin B6 supplements could reduce the symptoms of premenstrual syndrome (PMS), but conclusions are limited due to the poor quality of most studies [22].
    
    Who: women with premenstrual syndrome
    Effect: agency judgement: promising, not established
    Certainty: ODS relies on Wyatt 1999 and an RCT of 94 women, 80 mg (Kashanian 2007, PMID 17187801, abstract not in the corpus).
    NIH Office of Dietary Supplements, Vitamin B6 Fact Sheet for Health Professionals · checked 2026-10-07 · we read the section
17. ev-b6pms-17 · Position of an expert body · agency fact sheet summarizing an RCT · n = 94
    A more recent double-blind, randomized controlled trial in 94 women found that 80 mg pyridoxine taken daily over the course of three cycles was associated with statistically significant reductions in a broad range of PMS symptoms, including moodiness; irritability; forgetfulness; bloating; and, especially, anxiety [23].
    
    Who: 94 women with PMS
    Effect: 80 mg/day for 3 cycles: lower moodiness, irritability, forgetfulness, bloating and anxiety
    Certainty: The primary RCT (17187801) has no abstract in the corpus; the effect figure is not printed here.
    NIH Office of Dietary Supplements, Vitamin B6 Fact Sheet for Health Professionals · checked 2026-10-07 · we read the section
18. ev-b6pms-18 · Position of an expert body · agency fact sheet · n = —
    However, chronic administration of 1–6 g oral pyridoxine per day for 12–40 months can cause severe and progressive sensory neuropathy characterized by ataxia (loss of control of bodily movements) [10,30-33].
    
    Who: people taking high-dose pyridoxine supplements long term
    Effect: 1-6 g/day for 12-40 months: severe progressive sensory neuropathy with ataxia
    Certainty: Neuropathy has also been described below 500 mg/day, as ODS writes further.
    NIH Office of Dietary Supplements, Vitamin B6 Fact Sheet for Health Professionals · checked 2026-10-07 · we read the section
19. ev-b6pms-19 · Position of an expert body · agency fact sheet · n = —
    Based on limitations in the data on potential harms from long-term use, the FNB halved the dose used in these studies to establish a UL of 100 mg/day for adults.
    
    Who: adults
    Effect: US UL 100 mg/day (FNB); PMS trial doses 50 to 300 mg/day
    Certainty: UL does not apply to treatment under a physician's supervision.
    NIH Office of Dietary Supplements, Vitamin B6 Fact Sheet for Health Professionals · checked 2026-10-07 · we read the section
20. ev-b6pms-20 · Position of an expert body · scientific opinion based on systematic reviews · n = —
    From the midpoint of the range of these two ULs and rounding down, a UL of 12 mg/day is established by the Panel for vitamin B6 for adults (including pregnant and lactating women).
    
    Who: adults including pregnant and lactating women
    Effect: EU UL 12 mg/day; critical effect peripheral neuropathy
    Certainty: The bodies differ by 8-fold (US 100 mg, EU 12 mg); RCT doses for PMS are beyond the EU limit.
    EFSA NDA Panel, EFSA Journal, 2023 · checked 2026-10-07 · we read the abstract
21. ev-b6pms-21 · Position of an expert body · agency fact sheet · n = —
    Some research also indicates that pyridoxine supplementation (200 mg/day for 12–120 days) can reduce serum concentrations of phenytoin and phenobarbital, possibly by increasing the drugs' metabolism [33,38].
    
    Who: people taking antiepileptic drugs
    Effect: pyridoxine 200 mg/day for 12-120 days may reduce serum phenytoin and phenobarbital
    Certainty: For women on antiepileptics: high doses of B6 only with a doctor.
    NIH Office of Dietary Supplements, Vitamin B6 Fact Sheet for Health Professionals · checked 2026-10-07 · we read the section
22. ev-b6pms-22 · Randomized controlled trial(s) · randomized controlled trial, no placebo · n = 180
    However, a significant reduction in the overall score of MENQOL was not noticed before and after the treatment of pyridoxine and ascorbic acid (p = 0.3724 and p = 0.0732).
    
    Who: postmenopausal women with mild cognitive impairment, India; pyridoxine, ascorbic acid or no drug
    Effect: overall MENQOL change with pyridoxine p = 0.3724 (not significant); homocysteine lowered
    Certainty: Menopausal symptoms are a secondary outcome; control without placebo.
    Naunyn Schmiedebergs Arch Pharmacol, 2025 · checked 2026-10-07 · we read the abstract
23. ev-b6pms-23 · Observational data · cross-sectional study · n = 262
    After adjustment for age, body mass index, menopausal status, and background factors significantly related to VMS, only vitamin B6 (VB6) was significantly related to severity of HF (adjusted odds ratio per 10 μg/MJ in VB6 intake, 0.92; 95% confidence interval, 0.86-0.97).
    
    Who: women aged 40-65 at first visit to a menopause clinic, Japan
    Effect: adjusted OR 0.92 (95% CI 0.86 to 0.97) per 10 mcg/MJ vitamin B6 intake for hot flush severity
    Certainty: Cross-sectional: does not show causality; OR is odds. No RCT of B6 specifically for hot flashes was found.
    Climacteric, 2019 · checked 2026-10-07 · we read the abstract