Chaste tree (Vitex agnus-castus) is widely used to relieve symptoms of premenstrual syndrome (PMS), including PMS Type C, which is characterized by symptoms such as cravings, headaches, and mood swings thought to be associated with fluctuations in blood sugar and estrogen dominance. The use of chaste tree for PMS is supported by both traditional European herbal medicine and modern clinical research. Its mechanism is believed to involve modulation of the hypothalamic-pituitary axis, leading to a reduction in prolactin levels and balancing the ratio of estrogen to progesterone, which can help alleviate PMS symptoms.

Several randomized, placebo-controlled clinical trials have demonstrated that chaste tree extract can be effective in reducing the severity of overall PMS symptoms, including irritability, mood swings, headaches, and breast tenderness. A meta-analysis published in 2017 concluded that Vitex agnus-castus is more effective than placebo for PMS symptom relief. However, specific studies focusing exclusively on PMS Type C are limited, and most research evaluates PMS as a whole rather than by subtypes.

In summary, the use of chaste tree for PMS, including PMS Type C, is justified by a moderate level of scientific evidence. While more targeted research on PMS Type C would strengthen the evidence base, the existing data and traditional use support its role as a natural remedy for PMS symptom relief.