Chasteberry for Treatment of Menstrual Problems

Chaste tree berry (Vitex agnus-catus) or monk's pepper, is the fruit of the chaste tree. It is thought that the name chaste berry comes from the Middle Ages when monks reportedly used this fruit to decrease their sexual desire. This would help them avoid sex so they could remain chaste. Although there may not be a lot of evidence to support this use of chaste berry it points to the potent hormonal effects of this plant.

Chasteberry contains many phytochemicals including flavonoids that are thought to have many positive effects on your health. Several different types of flavonoids have been found in chasteberry. It has been shown that some of these flavonoids can influence certain hormone levels in your body especially prolactin, progesterone and to a certain extent estrogen.

Chasteberry has been used for centuries to treat several menstrual problems. It works mainly by its ability to influence certain hormone levels in your body.

Chaste tree berry cutting
Westend61 / Getty images


At low doses, chasteberry may increase your body's production of prolactin. Chasteberry has traditionally been used in women who are breastfeeding to increase their milk supply. However, there is not enough evidence to support this use and some authorities strongly recommend against its use in breastfeeding women.

At higher doses, studies suggest that chasteberry can decrease your prolactin levels. Even a slight increase in your prolactin levels (which commonly happens in response to stress) is thought to contribute to cyclic breast pain. It can also cause changes in your menstrual cycle that can affect your ovulation and your period.


Chasteberry is thought to increase the level of progesterone in your body. Certain conditions result from an improper balance of estrogen and progesterone.

What Conditions Does Chasteberry Help?

There has been considerable research mostly from Europe suggesting the effectiveness of chasteberry in treating the symptoms of:

  • Premenstrual syndrome
  • Cyclic mastalgia (breast tenderness)
  • Infertility due to elevated prolactin or inadequate progesterone (luteal phase disorder)

Although lacking clinical evidence as it its effectiveness, chasteberry has also traditionally been used to treat:

For each of these conditions, the therapeutic effect of chasteberry is thought to be due to its ability to either decrease prolactin or increase progesterone to restore proper hormonal balance in your body.

How Much Chasteberry Should I Take?

The therapeutic dose of chasteberry depends on the brand and the formulation you chose. Chasteberry is available in liquid, capsules, and tablets. Most clinical trials used a dose of 20-40 mg/day although some clinical trials have used doses as high as 1800 mg/day. Problems associated with elevated prolactin may need higher doses. You should discuss the use of chasteberry with your healthcare provider.

What Do I Need To Consider Before Trying Chasteberry?

While chasteberry is not associated with any serious side effects, it can cause dizziness, abdominal cramping, nausea, fatigue, dry mouth, and skin reactions. It is also possible to see some changes in your period when you start taking chasteberry.

Because chasteberry can alter progesterone and possibly estrogen levels in your body, women with hormone-related conditions such as breast cancer should not use chasteberry. Also, because chasteberry affects your dopamine system if you are taking medications for Parkinson's disease such as selegiline, amantadine, and levodopa should not use chasteberry. If you are pregnant it is recommended that you do not use chasteberry.

It is also very important to understand that chasteberry may decrease the effectiveness of the combination hormonal contraceptives. In other words, taking chasteberry while using the oral contraceptive pill, the contraceptive patch, or Nuvaring for birth control increases the chance that you could get pregnant.

Always tell your healthcare provider about any herbs, OTC medications, and vitamin or supplements you are taking.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Die MV, Burger H, Teede H, Bone K. Vitex agnus-castus extracts for female reproductive disorders: A aystematic review of clinical trialsPlanta Medica. 2012;79(07):562-575. doi:10.1055/s-0032-1327831.

  2. National Center for Complementary and Integrative Health. Chasteberry.

  3. Drugs and Lactation Database (LactMed). Chasteberry.

By Tracee Cornforth
Tracee Cornforth is a freelance writer who covers menstruation, menstrual disorders, and other women's health issues.