Limited evidenceWomen's health

Cramp Bark

A traditional antispasmodic bark with real smooth-muscle activity in the laboratory but essentially no controlled human data for menstrual cramps. The reputation rests on 19th-century practice, not on trials.

Evidence last reviewed: August 2026

What the science says

Menstrual cramps Limited evidence
No modern randomized trial has tested Viburnum opulus for dysmenorrhea. A phytochemistry and pharmacology review documents antispasmodic and anti-inflammatory activity in cell and animal models only.
Smooth muscle relaxation Limited evidence
The one modern human trial of a Viburnum opulus (gilaburu) extract tested it against tamsulosin for passing distal ureteral stones and reported comparable expulsion rates. That is indirect support for a smooth-muscle effect, not evidence for menstrual pain.

Dosage & safety

Studied doseNo trial-established dose for cramps. Traditional use is 2-4 g of dried bark as a decoction, or 4-8 ml of tincture, taken two to three times daily during pain.

SafetyContains salicylates, so avoid with aspirin sensitivity and use caution with anticoagulants. Not established as safe in pregnancy or breastfeeding. Kidney irritation has been raised as a theoretical concern with prolonged use.

Scientific references

Viburnum opulus L.-A Review of Phytochemistry and Biological Effects
Kajszczak D, Zakłos-Szyda M, Podsędek A — Nutrients, 2020
Gilaburu extract (Viburnum opulus Linnaeus) is as effective as Tamsulosin in medical expulsive therapy of distal ureteral calculi
Gok B, Tarik Atik Y, Uysal B, Koc E, Tastemur S, İbrahim Cimen H — Int J Clin Pract, 2021

Where to buy

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