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Materia Medica
Cramp bark is the dried bark of Viburnum opulus, a deciduous shrub of the Adoxaceae family native to Europe and North America. It has been used for centuries as a reliable antispasmodic, particularly for menstrual and other smooth-muscle cramping.
Actions & Energetics
Warm, dry, bitter, and mildly pungent. Traditionally regarded as a specific antispasmodic for the uterus and other smooth muscle. Eclectic physicians of the nineteenth century considered it one of their most reliable remedies for cramps. Actions include antispasmodic, mild sedative, and astringent.
Botanical Description
A multi-stemmed deciduous shrub reaching 2–4 meters, with lobed maple-like leaves and flat-topped clusters of white flowers. The outer flowers of each cluster are larger and sterile; the inner ones are fertile and develop into bright red berries. The bark is collected from the stems in spring or fall. The plant prefers moist woodland edges and is widely cultivated as an ornamental (snowball bush).
Traditional Indications
Primary traditional use for spasmodic menstrual cramps and uterine pain. Historical use for other smooth-muscle spasms, including intestinal and bronchial. Eclectic physicians also employed it for threatened miscarriage and as a partus preparator. Berries have separate culinary and folk uses in some traditions but are not equivalent to the medicinal bark.
Preparations & Dosage
Decoction of the bark: 1–2 tsp simmered in water. Tincture (1:5): 2–4 ml. Powdered bark: 1–3 g. Best prepared as a decoction because the bark is woody. Often combined with other uterine or nervine herbs in traditional formulas.
Constituents
Iridoid glycosides (including viburnin), scopoletin, and tannins. The antispasmodic activity is attributed primarily to the iridoid content. The bark contains little of the cyanogenic compounds found in some related species.
Modern Research
Limited formal clinical trials exist. Preclinical studies support smooth-muscle relaxant effects. Traditional use for menstrual cramps is long-standing and well documented in both Indigenous North American and European herbal practice. The bark was official in the United States National Formulary into the mid-twentieth century.
History, Folklore & Spiritual Use
Used by several Native American nations, including the Meskwaki and Iroquois, for menstrual and other cramping. Adopted and further developed by nineteenth-century Eclectic physicians, who regarded it as a specific for uterine spasm. In Slavic cultures the related plant (kalina) holds deep symbolic meaning connected to love, blood, and protection. The English name cramp bark reflects its primary traditional reputation. It remains a classic antispasmodic in modern Western herbalism.
Summary
Cramp bark is a classic antispasmodic whose traditional reputation for relieving menstrual and other smooth-muscle cramps is both historically deep and mechanistically plausible. Its place in Indigenous, Eclectic, and contemporary Western practice makes it one of the most specific and reliable uterine herbs in the North American and European materia medica.
Educational information only. Consult a qualified practitioner for personal use.