Chinese Chastetree (Vitex negundo) is sometimes used in traditional medicine systems for women's health, but the more widely studied species for premenstrual syndrome (PMS), including PMS Type C (which is characterized by cravings, especially for sweets, and symptoms like fatigue and headaches), is Vitex agnus-castus (commonly known as chasteberry or monk’s pepper). Scientific studies have primarily focused on Vitex agnus-castus, which has shown some efficacy in reducing overall PMS symptoms, likely due to its effects on dopamine receptors that modulate prolactin secretion. This hormonal modulation may help with certain PMS symptoms.

For Vitex negundo, research is more limited. Some animal and preliminary human studies suggest anti-inflammatory, analgesic, and possible hormonal effects, but direct clinical trials examining its specific use for PMS Type C are sparse. Most evidence comes from broader studies on PMS or from analogies to Vitex agnus-castus. Therefore, while there is some scientific rationale and early evidence supporting the use of Chinese Chastetree for PMS symptoms, the direct evidence for PMS Type C is moderate at best. The rating reflects that some scientific support exists, but it is not as robust or specific as for its Western counterpart.