Historical or traditional use (may or may not be supported by scientific studies): Wood betony was used in European folk herbalism as a remedy for respiratory tract inflammation, heartburn, urinary tract inflammation, varicose veins, intestinal worm infestations, and failure to thrive.1 It was considered a calming remedy and was used for headaches as well as some forms of neuralgia, including shingles.2

Active constituents: The active constituents of wood betony have not been clearly identified. The tannins, alkaloids, glycosides, and volatile oil found in this plant and its cousins may all contribute to its activity. Almost no research has been conducted on wood betony. Some Russian research in humans apparently suggests it may promote lactation, though the details of these studies are not readily available.3 4

How much is usually taken? A tea of wood betony can be made by steeping 1 to 2 tsp dried leaf and flower in a cup of water for 15 minutes. One or two cups of this tea can be drunk per day.5 Though generally better between meals, it can be taken with food for convenience or if there is any gastrointestinal upset.

Are there any side effects or interactions? There are no known adverse effects from use of wood betony other than occasional mild gastrointestinal upset. Its safety in pregnancy and breast-feeding is generally unknown, though as noted above it has been studied in Russia as a way to increase lactation.

At the time of writing, there were no well-known drug interactions with wood betony.

References
1-5. Lust J., The Herb Book. New York: Bantam Books, 1974:116.
2. Mills SY., Out of the Earth: The Essential Book of Herbal Medicine. Middlesex, UK: Viking Arkana, 1991:576.
3. Stegailo EA, Lebedeva IM, Aronova BN, et al. Treatment of hypogalactia with an extract of the betonica hedge nettle. Akush Ginekol (Mosk) 1980;(2):19–20 [in Russian].
4. Bakhalova NV, Kharmats DA. Effect of the milk from mothers receiving methylergometrine and hedge nettle extract on the physical development of the newborn infant. Zdravookhr Kirg 1977;(2):28–31 [in Russian].