Vitamin B6 (in its active form, pyridoxal 5’-phosphate) has been investigated for its potential to alleviate symptoms of premenstrual syndrome (PMS), including the “Type D” variant, which is characterized by depressive symptoms such as mood swings, irritability, and low mood. The rationale for its use is primarily based on its role as a cofactor in the synthesis of neurotransmitters such as serotonin and dopamine, which are implicated in mood regulation. Research suggests that women with PMS may have altered neurotransmitter metabolism, and vitamin B6 supplementation may help correct these imbalances.

Several randomized controlled trials and meta-analyses have assessed the efficacy of vitamin B6 for PMS symptoms, with some showing a modest benefit, particularly for emotional and affective symptoms. For example, a 1999 meta-analysis by Wyatt et al. concluded that vitamin B6 at doses up to 100 mg/day may be more effective than placebo in relieving overall PMS symptoms, especially mood-related ones. However, the quality of evidence is limited by small sample sizes, methodological differences, and potential for bias. Authoritative reviews, such as those by the Cochrane Collaboration, note that while there is some evidence of benefit, it is not strong or consistent enough to warrant a high level of clinical recommendation.

In summary, the use of vitamin B6 for PMS Type D is supported by some scientific evidence, particularly for mood symptoms, but the evidence is modest (rated 2/5) and not unequivocal.