A 1986 German clinical trial over a three month period with 36 PMS patients reported positive results in physical and psychological symptoms. A dose of 40 drops a day of a chaste tree berry tincture, taken over a three month period, produced a reduction in headaches, breast tenderness and pressure, bloating, and fatigue. Improvement in anxiety, mood swings, and other psychological symptoms were also reported.

In a 1990 German clinical drug monitoring study of the efficacy and safety of long-term treatment with a chaste tree fruit tincture, 1571 women with menstrual disorders including corpus-luteum insufficiency and PMS were followed for a period of 7 days to six years (average 147.6 days). The dose was 40 drops of a chaste tree berry tincture once a day taken on an empty stomach in the morning with water. In 90 percent of patients, the treatment eliminated or alleviated symptoms of PMS. Results for 465 patients were rated very good, 714 good, 220 satisfactory, 110 unsatisfactory, and in 62 cases no data was available. Adverse reactions were reported for 30 patients (1.9 percent), including 12 cases of nausea, gastric symptoms and diarrhea, and a single allergic reaction.

A clinical survey of German gynecologists published in 1992 evaluated the effect of a chaste-tree preparation on 1542 women diagnosed with PMS. Treatment of 40 drops (tincture) daily lasted an average of 166 days. Both physicians and patient assessed efficacy, with 90 percent reporting relief of symptoms, after an average treatment duration of 25.3 days. Two percent reported side effects, mostly gastrointestinal in nature.

In order to test the effectiveness and tolerability of chaste tree berry capsules, a research group in Germany conducted a controlled, double-blind study on the use of the preparation compared with vitamin B-6. The study was conducted in sixteen centers involving 175 female patients, 85 of whom received the chaste tree preparation, while 90 received vitamin B-6. Effectiveness was assessed by both the patient and physician at the end of the trial. Treatment was continued for three menstrual cycles. Those who received the chaste tree fruit dried extract (3.5-4.2 mg) took one capsule and one placebo capsule per day. Those in the vitamin B-6 group, received one capsule of placebo twice daily on days 1 to 15 and one capsule of pyroxidine-HCL (100 mg) twice daily from the 16th through the 35th days of the cycle.

Using a standard clinical global impression scale to record results, the researchers found that those who received the chaste tree extract had a marked reduction of PMS symptoms such as breast tenderness, edema, tension, headache, constipation and depression. It was found useful in 80 percent of the women, and results were rated by practitioners as excellent in over 24 percent of cases. Twelve patients in the chaste tree berry extract treatment group reported gastrointestinal complaints, transitory headaches, or mild skin reactions. These adverse effects were transient in nature. The researchers concluded that the dried berry extract of chaste tree was safe and effective in the treatment of PMS.

Modern Applications

In Germany, the use of phytomedicines in the treatment of menstrual disturbances is often preferred over conventional treatment, if no contraceptives are indicated. Steroidal hormones are often considered unnecessary, and individual treatment initiated once differentiation has been made between cyclic and acyclic bleeding difficulties. A benefit of chaste tree treatment is the relative lack of side effects compared with treatment with steroidal hormones. Another benefit is that the price of chaste tree preparation therapy is far below that of conventional treatment methods. The German Commission E, a body of German health regulatory authorities who produce regulations on herb products in Germany has produced a monograph on chaste tree berries. The monograph on chaste tree berries allows use of preparations for menstrual disorders due to rhythmic disorders of menstruation, mastodynia (pressure and swelling in the breasts), and premenstrual syndrome. Preparations include alcoholic extracts of the pulverized fruits (tincture) formulated to an average daily dose equivalent to 30-40 mg of the fruits. No contraindications are listed. While no interactions with other drugs are reported, animal experiments indicate the possibility of interference with dopamine-receptor antagonists. Side effects noted include too early menstruation following delivery (resulting from activation of the pituitary), as well as rare instances of itching and rashes. Chaste tree preparations are contraindicated during pregnancy.