This herb can be found in pill form in most health stores. Follow the package instructions for the specific dosage. Chasteberry may help relieve symptoms of premenstrual syndrome, although scientific evidence is currently limited. However, it has not been proven to reduce menopausal symptoms, increase lactation, or increase fertility.  Chasteberry has been shown to influence estrogen levels. However, the exact nature and level of the effect has not been widely established.  Avoid taking chasteberry if you are using: birth control pills, antipsychotic drugs, medications used to treat Parkinson's disease, or Metoclopramide, a dopamine-affecting drug. Phytoestrogens act like an estrogen substitute in the body and occur naturally in several plants and herbs. Consider using phytoestrogens if you're trying to alleviate symptoms of low estrogen levels, or menopause. Take phytoestrogens in moderation. You may actually want to avoid phytoestrogens if you're trying to conceive. Phytoestrogens have been linked to infertility and developmental problems, although you would need to consume massive quantities of these foods to ingest clinically significant levels of phytoestrogens. Foods and herbs that contain phytoestrogens include:  legumes: soybeans, peas, pinto and lima beans fruits: cranberries, prunes, apricots herbs: oregano, sage, licorice whole grains flaxseed vegetables: broccoli and cauliflower Several herbal teas or tisanes may increase your estrogen levels or provide relief for symptoms of menopause or premenstrual syndrome without affecting your estrogen levels. Steep the herbs in a cup of hot water for five minutes.  Black and green tea. Black and green teas contain phytoestrogens.  Dong quai (Angelica sinensis). Used in Chinese traditional medicine, this herb may reduce symptoms of premenstrual syndrome. Do not use it if you use blood-thinning drugs like warfarin. Red clover. Red clover contains isoflavones, which may help reduce symptoms of menopause or premenstrual syndrome. Flax seeds have one of the...

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Write a summary of the previous text in Vietnamese:
Dùng thực phẩm bổ sung chasteberry. Chọn thực phẩm nhiều phytoestrogens. Làm trà thảo mộc. Ăn hạt lanh.