Agnus castus - also known as Chaste tree, Hemp tree, Wild lavender, Monk's pepper tree and by its Latin name Vitex agnus castus - is a product traditionally used for the relief of premenstrual symptoms such as irritability, mood swings, breast tenderness, bloating and menstrual cramps.
Agnus castus has been used for several centuries. The extract is derived from dried, pulverised, peppercorn-sized fruit of the chaste tree, a small woody shrub that grows along riverbanks and hillsides primarily in Mediterranean regions and Central Asia.
Agnus castus is registered with the UK medicines regulator MHRA under the Traditional Herbal Registration (THR) scheme. This does not mean the regulator has tested products, which contain Agnus castus, to prove it works or that claims about it have been verified by clinical studies. However, it does mean that Agnus castus has been confirmed as being used as a traditional medicine for at least 30 years - and 15 years in the EU.
Registration also confirms that the product manufacturer is meeting established standards of safety and quality.