Researchers indicate that Vitex agnus‑castus, commonly called chasteberry, may support fertility, ease certain premenstrual and menopausal complaints, and act as a deterrent to some insects such as mosquitoes.
Vitex agnus‑castus is a widely used herbal remedy taken for multiple health concerns.
It’s most frequently applied for:
- premenstrual syndrome (PMS)
- menstrual irregularities
- infertility
- acne
- menopausal symptoms
- breastfeeding difficulties
It’s also promoted as protection from insect bites and as a potential cancer preventative, among other claims — though not every purported benefit has strong scientific backing.
Below are the benefits supported by research, along with some common misconceptions, about Vitex agnus‑castus.
What is Vitex agnus‑castus?
Vitex is the largest genus in the Verbenaceae family and contains around 250 species globally (1).
Vitex agnus‑castus is the species most often employed medicinally.
The fruit of Vitex agnus‑castus, known as chasteberry or monk’s pepper, is roughly the size of a peppercorn and grows on the chaste tree. The tree acquired its name from historical use when its fruit was thought to suppress male libido in medieval times (2).
Various parts of the plant, including the fruit, are commonly used in traditional herbal medicine to address a spectrum of health issues.
For example, Vitex agnus‑castus is traditionally used for:
- PMS
- menopausal complaints
- fertility problems
- other female reproductive conditions
Its use for these purposes dates back to ancient Greek medicine (2).
In Turkish traditional medicine it’s additionally used as a digestive aid, antifungal, and anxiolytic (3).
Summary: Vitex agnus‑castus is a plant frequently used as a traditional remedy for several conditions, most notably PMS, menopausal complaints, and fertility-related issues.
Improves conditions affecting women’s reproductive health
Vitex agnus‑castus is best known for benefits related to the female reproductive system.
Relieves premenstrual syndrome (PMS) symptoms
One of the most researched qualities of Vitex agnus‑castus is its potential to lessen PMS symptoms.
Reported improvements include:
- constipation
- irritability
- low mood
- migraines
- breast pain and tenderness
Scientists think vitex may act by lowering prolactin levels, which helps rebalance hormones such as estrogen and progesterone and can reduce PMS symptoms (4).
In one trial, women with PMS took Vitex agnus‑castus for three consecutive cycles; 93% of participants reported symptom improvement, including reductions in depression, anxiety and cravings — though that study lacked a control group, so placebo effects can’t be excluded (5).
In two smaller randomized trials, women received 20 mg daily of Vitex agnus‑castus or placebo for three cycles. Twice as many women in the vitex group reported relief from irritability, mood swings, headaches and breast fullness compared with placebo (6, 7).
Vitex agnus‑castus also seems to ease cyclic mastalgia (menstrual-related breast pain) and may be as effective as standard drug treatments but with fewer side effects (8, 9, 10).
Nevertheless, two recent reviews suggest that while vitex likely helps with PMS, its effects may be overestimated and higher-quality trials are needed (11, 12, 13).
May lessen menopausal symptoms
The hormone‑modulating properties of Vitex agnus‑castus may also reduce some menopausal complaints.
In one small study, vitex essential oils given to 23 menopausal women improved mood and sleep, and some women even resumed menstruation (14).
In a related follow‑up where 52 pre‑ and postmenopausal women used a vitex cream, 33% reported major improvement and 36% reported moderate improvement in symptoms like night sweats and hot flashes (14).
However, a larger recent double‑blind randomized controlled trial that compared a daily tablet combining vitex and St. John’s wort with placebo found no advantage for the supplement in reducing hot flashes, depressive symptoms, or other menopausal issues after 16 weeks (15).
Note that many positive reports involve products mixing vitex with other herbs, making it hard to determine vitex’s individual contribution (16).
May support fertility
Vitex might boost fertility by lowering prolactin levels (17).
This could be particularly helpful for women with luteal phase defect (a shortened second half of the cycle), a condition often linked to elevated prolactin and reduced fertility.
In one trial, 40 women with high prolactin were treated with either 40 mg of Vitex agnus‑castus or a conventional drug; vitex reduced prolactin as effectively as the pharmaceutical (18).
In a study of 52 women with luteal phase defect, 20 mg of vitex lowered prolactin and lengthened the luteal phase, while placebo produced no change (19).
Another trial provided 93 women (who had not conceived in the prior 6–36 months) with a supplement containing Vitex agnus‑castus or placebo. After three months, hormone balance improved in the vitex group and 26% of them became pregnant versus 10% in the placebo group (20).
Again, that product contained other components, so isolating vitex’s role is challenging.
Irregular cycles can also impede conception; three more trials indicate vitex improves menstrual regularity compared to placebo (21, 22, 19).
Summary: Vitex agnus‑castus may ease PMS and some menopausal complaints, and by lowering prolactin and stabilizing cycles it could enhance fertility, though study findings vary.
Helps prevent insect bites
Vitex extracts may provide protection against several insects.
One study found an extract from vitex seeds repelled mosquitoes, flies, ticks, and fleas for around six hours (24).
Another trial showed a spray containing vitex and other plant extracts protected against head lice for at least seven hours (25).
Research also indicates vitex may kill lice larvae and interfere with adult lice reproduction (25, 26).
Summary: Vitex agnus‑castus may help deter insects such as mosquitoes, flies, ticks, fleas and head lice.
Other possible benefits
Vitex has been linked to several additional potential effects, including:
- Fewer headaches. In one non‑controlled study, women prone to menstrual migraines who took vitex for three months reported a 66% reduction in headaches during their cycles (28), but the absence of a control group limits conclusions.
- Antibacterial and antifungal activity. In vitro tests show vitex essential oils can inhibit certain fungi and bacteria, including Staphylococcus and Salmonella species (29, 30). Note that essential oils are not meant for ingestion, and oral vitex supplements are unlikely to prevent infections.
- Anti‑inflammatory effects. Laboratory and animal work suggests vitex compounds have anti‑inflammatory activity, though not stronger than aspirin (31, 32).
- Bone healing. A study found women with fractures who received a combination of vitex and magnesium exhibited slightly improved markers of bone repair versus placebo (35).
- Seizure reduction. Animal studies suggest vitex might lower seizure susceptibility (36, 37).
Overall, evidence for these additional uses is limited and further research is necessary.
Summary: Vitex shows promise for several other effects, but current evidence is weak and more studies are required before firm claims can be made.
Common myths
Although vitex has a long history of traditional use for many conditions, several popular claims lack solid scientific support.
Common unsupported uses include:
- Increasing breastmilk. An older study suggested vitex may raise milk supply, but overall evidence is sparse and controversial (38).
- Pain relief. Animal studies indicate vitex can numb pain receptors, but human studies are lacking (39).
- Treating endometriosis. Although vitex might correct hormonal imbalances theoretically relevant to endometriosis, no clinical trials confirm effectiveness.
- Preventing baldness. Claims that vitex’s hormone effects stimulate male hair regrowth are unsupported by research.
- Acne treatment. A few older studies suggested vitex could clear acne faster than standard therapies, but those are dated and not confirmed by modern trials (40).
Summary: While vitex is used as an alternative remedy for various conditions, many purported benefits are not substantiated by current research.
Potential side effects
Vitex agnus‑castus is generally regarded as safe when used appropriately.
Reported safe dosing ranges include 30–40 mg of dried fruit extract, 3–6 g of dried herb, or about 1 g of dried fruit daily (9).
Side effects are usually mild and reversible, and may include (41):
- nausea
- upset stomach
- mild skin rash
- increased acne
- headache
- heavier menstrual bleeding
Pregnant and breastfeeding women are advised to avoid vitex because its effects on infants are not well established (42).
Vitex may also interact with:
- antipsychotic medications
- oral contraceptives
- hormone replacement therapy
For these reasons, consult your healthcare provider before starting vitex, especially if you take prescription meds (9).
Summary: Vitex agnus‑castus is generally well tolerated with mild, reversible side effects. Pregnant or nursing women and those on certain medications should avoid it or seek medical advice first.
The bottom line
Vitex agnus‑castus, or chasteberry, may aid fertility and reduce some symptoms of PMS and menopause, and it may help repel certain insects.
Most other claimed uses lack strong scientific support.
It can cause mild gastrointestinal or other side effects but is considered safe for most people when used properly.
If you’re considering trying Vitex agnus‑castus, discuss it with your doctor first — particularly if you are:
- pregnant
- breastfeeding
- taking prescription medications
Leave a Reply
You must be logged in to post a comment.