Recommended dose: 1-2ml (20-40 drops) in a little water three times a day before meals.

Traditional use:  The berries of Vitex agnus-castus L. (chaste tree; chasteberry) are a popular herbal treatment for a range of female reproductive conditions in Anglo-American and European practice. Vitex is considered as one of the most important herbs for female health due to balancing effect on the ovarian hormonal production. (https://pubmed.ncbi.nlm.nih.gov/23136064/) 

For PMS, the herb should be taken for a few months before the full benefits are achieved and the bloating, breast swelling and tenderness, irritability, and depression are all reduced.

Clinical evidence: Double-blind placebo-controlled studies indicate that one of the most common premenstrual symptoms, i.e. premenstrual pain, is beneficially influenced by Agnus-castus extract. In addition, numerous other studies indicate that Agnus-castus extracts have also beneficial effects on other psychic and somatic symptoms of the Premenstrual syndrome (PMS) (ref https://pubmed.ncbi.nlm.nih.gov/12809367/).

Warnings: Vitex suppresses prolactin production and lactation and it is not recommended for nursing mothers.