Cramp Bark
Viburnum opulus
Cramp bark is a traditional antispasmodic herb used to ease menstrual cramps and other forms of smooth-muscle tension.
Primary Use
Menstrual cramp relief
Common Forms
Tincture, Decoction
Typical Dose
2-5 mL
Time to Effect
2-4 weeks
Overview
Cramp bark is the bark of Viburnum opulus, a shrub long valued in Western herbalism for painful muscle tension, especially menstrual cramping. Herbalists have also used it for general spasmodic pain, tight shoulders, and tension patterns where muscles feel clenched or reactive.
Although modern clinical research is not extensive, cramp bark remains popular because its traditional use is very specific and consistent. It is often included in formulas for period pain, pelvic tension, and nervous muscular gripping. It is usually taken as a tincture or decoction because bark is not as convenient as leaf-based herbs.
How It Works
Cramp bark appears to have antispasmodic activity, meaning it may help relax involuntary or overly tense muscle tissue. It contains coumarins and other constituents that are thought to contribute to its traditional use for uterine and smooth muscle tension.
In practical terms, herbalists use it when the body feels locked into a pain-spasm cycle, especially around the menstrual cycle. It is not mainly a numbing herb; it is more about easing the gripping quality of cramping.
What It's Used For
Menstrual cramp relief
Cramp bark is widely used in traditional herbalism for dysmenorrhea and uterine spasm. Clinical evidence is limited, but its historical use for this exact purpose is strong.
Muscle spasm support
It may help with tension-related spasms beyond the pelvic area, including tight or cramping muscle patterns. Most evidence is traditional and observational.
Pelvic tension support
Herbal practitioners often use cramp bark when pain seems linked to constriction and spasm rather than inflammation alone. This can make it a useful formula herb in cycle support blends.
Nervous tension formulas
Because spasm and stress often overlap, cramp bark is sometimes combined with calming herbs. This use is traditional and individualized.
Dots indicate strength of research evidence (5 = strongest)
Disclaimer: This information is for educational purposes only and is not intended as medical advice. Always consult with a qualified healthcare provider before starting any new supplement, especially if you have a medical condition or take medications.
Last updated: March 2026