Black Haw
Name of plant:
Black haw
Traditional Lore :
Black haw (Viburnum prunifolium) is native to the eastern and central regions of North America, where its bark and roots were used medicinally by Indigenous peoples and later became established in European-derived American herbal practice. Traditional herbalists particularly valued the bark for women's health and reproductive complaints, including menstrual discomfort and difficulties associated with pregnancy, and it became an important remedy in nineteenth-century Eclectic medicine. The plant's dark, almost black mature fruits were also gathered as food, while its dense wood was useful for small implements and other practical purposes. Through its adoption into American herbalism, black haw developed a lasting reputation as one of the characteristic medicinal shrubs of the eastern North American woodland.
Family:
Adoxaceae — Moschatel family
(Formerly classified within Caprifoliaceae — Honeysuckle family)
Genus and species:
*Viburnum prunifolium* L.
Other names:
Black haw, Blackhaw, Blackhaw viburnum, Sweet haw, Sloe-leaved viburnum, Stag bush, Smooth blackhaw, *Viburnum prunifolium*
Brief introduction
Black haw is a deciduous shrub or small tree native to the eastern and central United States. It produces clusters of white flowers in spring followed by blue-black drupes that become edible when ripe. Its bark develops a distinctive dark, furrowed appearance with age.
The bark has a long history of use in North American herbal medicine, particularly in nineteenth-century Eclectic medicine. It became especially associated with women's reproductive health, including menstrual cramps, uterine discomfort, pregnancy-related cramping, and the prevention of miscarriage. The plant is closely related to other medicinal *Viburnum* species, including cramp bark (*V. opulus*), but should not be treated as interchangeable with them.
Traditional uses:
* Menstrual cramps and painful menstruation
* Uterine cramping and spasms
* Traditional support during pregnancy for uterine irritability
* Muscular cramps and spasmodic pain
* Traditional treatment of diarrhea and other gastrointestinal cramping
Historical use:
* Native North American traditions used black haw bark for gynecological and gastrointestinal complaints
* Nineteenth-century American Eclectic physicians adopted black haw as a uterine antispasmodic
* It was traditionally used for painful menstruation and uterine cramping
* Historical herbalists employed it during pregnancy for threatened miscarriage and uterine irritability
* Bark preparations were also used for muscle cramps, spasms, and gastrointestinal discomfort
Parts used and method of use:
* Root bark
* Stem bark
Used as:
* Decoction
* Fluid extract
* Tincture
* Powdered bark or encapsulated extract
Use in healing (modern herbal practice):
* Traditional support for dysmenorrhea
* Traditional antispasmodic for uterine cramping
* Traditional support for muscle cramps and spasms
* Historical use for pregnancy-associated uterine cramping
* Traditional treatment of gastrointestinal spasms
Black haw remains primarily a traditional herbal medicine. Modern clinical evidence is insufficient to establish efficacy for most of these indications.
Pharmacology and biochemistry:
* Scopoletin
* Salicin and related phenolic glycosides
* Coumarins and other phenolic compounds
Mechanisms:
* Coumarin and phenolic constituents may contribute to smooth-muscle-relaxing and antispasmodic activity
* Salicylate-related constituents may contribute to analgesic and anti-inflammatory effects
* Experimental studies suggest effects on smooth muscle and inflammatory pathways, although the precise mechanism responsible for traditional uterine use remains uncertain
Overall profile:
A traditional North American antispasmodic bark particularly associated with uterine and menstrual cramping. Its historical reputation is strong, but modern pharmacological and clinical evidence is comparatively limited, and its traditional use during pregnancy should not be assumed to establish safety.
Common dosage:
* Decoction: Approximately 1–2 g dried bark per cup, traditionally taken up to three times daily
* Tincture: Approximately 2–4 mL, up to three times daily in traditional herbal practice
* Fluid extract: Approximately 1–2 mL, up to three times daily, depending on concentration
* Powdered bark: Approximately 1–2 g per dose, traditionally used up to three times daily
Dosage varies considerably among historical preparations and modern extracts; standardized therapeutic dosing has not been established by modern clinical research.
Safety factors (including side effects):
* Black haw should not be used during pregnancy without direct medical supervision, despite its historical use for pregnancy-related cramping
* Large or prolonged doses may cause nausea, gastrointestinal upset, or other adverse effects
* Because the plant contains salicylate-related constituents, caution is appropriate in people sensitive to aspirin or salicylates
* Individuals taking anticoagulant or antiplatelet medicines should avoid medicinal doses without professional advice
* Long-term safety and the safety of concentrated extracts have not been adequately established
First aid / adverse reaction response:
* Nausea or gastrointestinal irritation: Discontinue use and seek medical advice if symptoms persist
* Signs of salicylate sensitivity such as wheezing, hives, or swelling: Discontinue use and seek urgent medical attention
* Unusual bleeding or bruising: Stop use and seek medical evaluation
* Suspected excessive ingestion: Contact a poison-control centre or seek medical attention
Drug interactions:
* Theoretical additive effects with aspirin and other salicylate-containing medicines
* Possible additive effects with anticoagulant and antiplatelet medicines
* Potential interaction with other analgesic or anti-inflammatory medicines
* General caution is appropriate with pregnancy, anticoagulation therapy, aspirin sensitivity, and other conditions in which bleeding or salicylate exposure is a concern
Horticultural requirements:
* USDA / Canadian zone: Approximately 4–9
* Soil pH: Approximately 5.0–7.5
* Light requirements: Full sun to partial shade
* Moisture: Moderate; prefers moist, well-drained soil but is relatively adaptable
* Other notes (growth habit, harvest timing, etc.):
* Deciduous shrub or small tree, commonly reaching approximately 3–6 m
* White flowers appear in flat-topped clusters during spring
* Blue-black fruits develop during late summer and autumn
* Bark is harvested primarily from mature stems or roots, traditionally during dormant periods
* Native to woodland margins, open forests, thickets, limestone areas, and upland sites of eastern and central North America
* Propagation is possible from seed, cuttings, or layering; seed may require stratification and can be slow to germinate
Sampling of clinical reports / studies:
* Modern controlled clinical trials specifically evaluating black haw for dysmenorrhea, uterine cramping, or threatened miscarriage are lacking or insufficient to establish efficacy.
* Pharmacological research on *Viburnum* species suggests antispasmodic, antioxidant, anti-inflammatory, and smooth-muscle effects, although evidence specific to *V. prunifolium* remains limited.
* Phytochemical investigations have identified coumarins such as scopoletin, phenolic compounds, salicylate-related constituents, and other secondary metabolites.
* Ethnobotanical and historical records provide substantial evidence for the use of black haw bark in North American herbal medicine, particularly for menstrual and uterine cramping.
* Overall assessment: Black haw is historically important as a uterine and general antispasmodic herb, but its medicinal reputation rests primarily on traditional and historical evidence rather than modern clinical trials. Its historical use in pregnancy warrants particular caution and should not be interpreted as evidence of modern obstetric safety.
Educational Use Only: The information presented on this page is provided for educational, historical, and informational purposes only. ArdNemeton na Tuatha and Bhùth Draoi do not provide medical advice. Always consult your physician and pharmacist before using any herb, mushroom, supplement, or botanical product for medicinal purposes. Traditional uses described herein do not constitute medical claims.
