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Herb library · Herb · Viburnum opulus

Cramp bark

The bark of the guelder rose, named for its long use for muscle and menstrual cramps. That use has not been tested in people. The only studies in people, from Turkey, gave an extract of the plant to adults passing small kidney stones, with encouraging but unblinded results.

Traditional use

Eclectic physicians in 19th-century America called the bark of the "high cranberry" cramp bark and used it for cramps and spasms, menstrual pain and in pregnancy. In Turkey the sour berries, called gilaburu, are made into a traditional fermented drink.

What studies show

  • Limited

    Passing small ureteral stones: in a prospective comparison of 86 adults with stones of 10 mm or less, a V. opulus extract (1,000 mg three times a day) passed stones about as often as the standard drug tamsulosin, with less need for extra pain relief. A retrospective review of 103 patients found more stones passed with the extract than with painkillers alone. Neither study was blinded or placebo-controlled.

  • Insufficient

    Menstrual and muscle cramps: no studies in people were found. In lab cells a cramp bark extract switched on a potassium channel involved in relaxing smooth muscle, which does not show an effect in a person.

Be careful of

Cautions

  • ConditionA kidney stone with fever, vomiting, a single kidney or pain that will not settle needs urgent medical care. In both studies the extract was given alongside a painkiller under a urologist's care.
  • PregnancyThe old herbal books recommend it in pregnancy, but no study of its safety in pregnancy or breastfeeding was found. Do not use it in pregnancy without your clinician.
  • NoteDo not confuse it with black haw (Viburnum prunifolium), a related bark sold for the same uses.
  • Ask a clinicianTalk with a clinician or pharmacist before using this if you take prescription medicines, are pregnant or breastfeeding, or are giving it to a child.

From the old books

What herbals and dispensaries of the past printed. History, in their words.

“High cranberry bark is a powerful antispasmodic, and, in consequence of this property, it is more generally known among American practitioners by the name of Cramp bark.”
Harvey Wickes Felter and John Uri Lloyd, King's American Dispensatory (1905), vol. 2, p. 2059. See the page of King's American Dispensatory, vol. 2, p. 2059 (opens in a new tab) · Read the full passage from King's American Dispensatory, vol. 2, p. 2059

Sources

  1. Gilaburu extract (Viburnum opulus Linnaeus) is as effective as tamsulosin in medical expulsive therapy of distal ureteral calculi (Int J Clin Pract, 2021) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
  2. The evaluation of the effectiveness of Gilaburu (Viburnum opulus L.) extract in the medical expulsive treatment of distal ureteral stones (Turk J Urol, 2019) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
  3. Diversity and probiotic potentials of lactic acid bacteria isolated from gilaburu, a traditional Turkish fermented European cranberrybush (Viburnum opulus L.) fruit drink (2014) — PubMed record (opens in a new tab) · NIH · read September 25, 2026
  4. KCNQ5 activation by tannins mediates vasorelaxant effects of barks used in Native American botanical medicine (FASEB J, 2022) — PubMed record (opens in a new tab) · NIH · read September 25, 2026

Reviewed September 25, 2026.