Chaste Tree (Vitex agnus-castus) Dosing for Adult Women
For premenstrual syndrome and cyclic mastalgia, the recommended dose is 20 mg daily of standardized Vitex agnus-castus extract (Ze 440 or BNO 1095), taken continuously for at least 3 months. 1
Premenstrual Syndrome (PMS)
- Standard dose: 20 mg daily of standardized extract (Ze 440) taken as a single dose 1
- A dose-finding study demonstrated that 20 mg was significantly superior to both 8 mg and placebo, while 30 mg provided no additional benefit over 20 mg 1
- Alternative formulation: 40 drops daily of liquid extract (BNO 1095, equivalent to 40 mg herbal drug) for 6 days before menses for 6 consecutive cycles 2
- Treatment duration: minimum 3 months (3 menstrual cycles) to assess efficacy 1, 3, 4
- Response rate: approximately 52% of patients experience ≥50% reduction in symptoms with the 20 mg dose 3
Cyclic Mastalgia
- Dose: 20-40 mg daily of standardized extract 5
- Treatment duration: 3 months minimum for optimal effect 5
- The extract reduces breast pain intensity and may lower elevated serum prolactin levels in reproductive-age women (18-45 years) 5
- Typical commercial preparations (Mastodynon®, Cyclodynon®) are effective when used for 3 ± 1 months 6
Menstrual Irregularities and Dysmenorrhea
- Same dosing as PMS: 20 mg daily of standardized extract 6
- Treatment for 3 months substantially decreases irregular cycles (from 9.1% to 0.1% of patients) and improves menstrual pain in 85.2% of patients 6
- For dysmenorrhea specifically, improvement in bleeding intensity occurs in 83.4% and menstrual pain improvement in 85.2% of patients 6
Hyperprolactinemia
- Dose range: 20-40 mg daily of standardized extract 7, 5
- VAC may be considered for mild hyperprolactinemia only, including idiopathic hyperprolactinemia, microprolactinoma, or drug-induced cases 7
- The mechanism involves dopamine D2 receptor activation in the anterior pituitary, inhibiting prolactin release 7
- Important caveat: Evidence for hyperprolactinemia treatment is limited to case reports and small series; no large randomized controlled trials exist 7
- This is not a substitute for standard dopamine agonist therapy (cabergoline) in clinically significant prolactinomas 8
Perimenopausal Symptoms
- No established dosing regimen exists specifically for perimenopausal symptoms 9
- The evidence base focuses primarily on reproductive-age women with PMS, mastalgia, and menstrual disorders 9, 6
- VAC has been studied historically for menopausal symptoms, but specific dosing recommendations are not well-established in modern literature 9
Administration Guidelines
- Timing: Take as a single daily dose, preferably in the morning 1, 3
- Duration before assessment: Evaluate treatment response after 3 months (3 menstrual cycles) 1, 3
- Continuation: If effective, treatment can be continued long-term with favorable safety profile 6, 5
Safety Profile
- VAC is well-tolerated with only mild and reversible adverse events 3, 5
- No serious adverse events reported in clinical trials 4, 5
- Adverse events are uncommon and do not typically require treatment discontinuation 3
Key Clinical Considerations
The standardized extracts Ze 440 and BNO 1095 are the only preparations with robust clinical trial evidence—other commercial preparations may not have equivalent efficacy 10. A meta-analysis found that women taking properly characterized VAC extracts were 2.57 times more likely to experience symptom remission compared to placebo (95% CI 1.52-4.35) 10. However, the majority of VAC studies cannot be used as evidence due to incomplete product characterization 10.
For hyperprolactinemia specifically, VAC should only be considered in mild cases where patients specifically request phytotherapy, as standard dopamine agonists (cabergoline 2 mg per week or less) remain the evidence-based first-line treatment 8, 7.