Magnesium citrate, a commonly used magnesium supplement, has some scientific support for its use in alleviating menstrual cramps (dysmenorrhea). Magnesium plays a crucial role in muscle relaxation and nerve function, and deficiencies in magnesium have been associated with increased muscle contraction and pain, which can contribute to menstrual cramps.

Several clinical studies have investigated the effects of magnesium supplementation on primary dysmenorrhea. A few randomized controlled trials have demonstrated that magnesium supplementation, compared to placebo, can reduce both the intensity and duration of menstrual pain in women suffering from cramps. Proposed mechanisms include a reduction in prostaglandin synthesis (compounds that trigger uterine contractions) and improved uterine muscle relaxation.

While magnesium citrate is absorbed well and often used in these studies, the overall quality and number of studies remain moderate, with some methodological limitations and variations in dosage and formulation. Most guidelines suggest magnesium as a possible adjunct treatment for menstrual cramps, particularly for women who do not respond to first-line therapies like NSAIDs. However, it is not considered a primary or universally accepted therapy. Larger, high-quality trials are still needed to confirm its effectiveness and optimal dosing.

In summary, there is scientific rationale and moderate evidence supporting the use of magnesium citrate for menstrual cramps, but it is not yet established as a first-line treatment.