Cramp Bark
Viburnum opulus L.; V. opulus var. americanum (Miller) Ait. Caprifoliaceae (honeysuckle family)
Cramp bark , guelder rose , snowball , squaw bush , cranberry tree , highbush cranberry , pimbina
 
Clinical Overview
Uses
Cramp bark has been used for painful menstruation and to prevent miscarriage.

Dosing
3 to 4 g/day.

Contraindications
Contraindications have not yet been identified.

Pregnancy/Lactation
Information regarding safety and efficacy in pregnancy and lactation is lacking. Avoid use.

Interactions
None well documented.

Adverse Reactions
No studies have been performed.

Toxicology
There are no studies of the toxicology of cramp bark.

 
Botany
Viburnum opulus is a large bush that is often grown ornamentally for its attractive white flowers. It is native to northern Asia and Europe. The American variety of V. opulus (also known as V. trilobatum ) has edible red berries while the European variety bears bitter fruit. An extensive study of Viburnum botany and pharmacognosy was published in 1932. 1 The trunk and root bark are the commonly used drug products.
 
History
The American variety was used by the Iroquois for prolapsed uterus after childbirth, 2 and other tribes recognized its use as a diuretic. 1 The Eclectic medical movement in the 19th century adopted cramp bark for dysmenorrhea and to prevent miscarriage. It was believed to be a stronger antispasmodic than the related Viburnum species V. prunifolium (black haw). 2 The bark was made official in the U.S. Pharmacopeia in 1894 and was included in the National Formulary in 1916. Widespread adulteration by mountain maple ( Acer spicatum ) and other Viburnum species led to confusion about the correct source plant. A later review surveyed the botanical, chemical, and pharmacological differences between black haw and cramp bark. 3
 
Chemistry
The coumarin scopoletin has been isolated from cramp bark. 4 The sesquiterpenes viopudial 5 and viburtinal 6 also have been found. The former compound was isolated by preparative gas chromatography, and the latter compound resulted from hydrolysis of undetermined esters. These compounds may be degradation products of iridoids, which have been reported from the leaves of this species. 7 Common plant triterpenes, such as alpha- and beta-amyrin, also have been reported; 8 cramp bark also contains substantial quantities of catechin tannins. 3
 
Uses and Pharmacology
Painful menstruation/miscarriage prevention   Early pharmacologic studies of cramp bark and black haw did not demonstrate activity in uterine preparations (see Black Haw monograph for details). Both scopoletin 4 and viopudial 5 have been determined to be responsible for the uterine relaxant activity of V. opulus . However, viopudial has not been found in black haw bark, which may account for its reputation for weaker activity.
Animal data   It has been shown that V. opulus and other species did indeed produce uterine relaxation in isolated rat tissues. 9
Clinical data   No clinical studies examining efficacy in humans have been performed.
 
Administration & Dosage
3 to 4 g/day.
 
Pregnancy/Lactation
Information regarding safety and efficacy in pregnancy and lactation is lacking. Avoid use.
 
Interactions
None well documented.
 
Adverse Reactions
Research reveals little or no information regarding adverse reactions with this product.
 
Toxicology
There are no studies of the toxicology of cramp bark.
 
References
 

1. Youngken HW. The pharmacognosy, chemistry and pharmacology of Viburnum . III. History, botany and pharmacognosy of Viburnum opulus L. Var. americanum . (Miller) Aiton. J Am Pharm Assoc . 1932;21:444-462.

 

2. Brinker F. A comparative review of Eclectic female regulators. J Naturopathic Med . 1998;7:11-26.

 

3. Hörhammer L, Wagner H, Reinhardt H. Chemistry, pharmacology, and pharmaceutics of the components of Viburnum prunifolium and V. opulus . Botan Mag (Tokyo). 1966;79:510-525.

 

4. Jarboe CH, Zirvi KA, Nicholson JA, Schmidt CM. Scopoletin, an antispasmodic component of Viburnum opulus and V. prunifolium . J Med Chem . 1967;10:488-489.

 

5. Nicholson JA, Darby TD, Jarboe CH. Viopudial, a hypotensive and smooth muscle antispasmodic from Viburnum opulus . Proc Soc Exp Biol Med . 1972;140:457-461.  PubMed

 

6. Brayer JL, Alazard JP, Thal C. A simple total synthesis of viburtinal. J Chem Soc Chem Commun . 1983;257-258.

 

7. Bock K, Jensen SR, Nielsen BJ, Norn V. Glycosides in Viburnum . Part 2. Iridoid allosides from Viburnum opulus . Phytochemistry . 1978;17:753-757.

 

8. Powers JL, Powers WE. Isolation and identification of alpha- and beta-amyrin from the bark of Viburnum opulus . J Am Pharm Assoc . 1940;29:175-178.

 

9. Jarboe CH, Schmidt CM, Nicholson JA, Zirvi KA. Uterine relaxant properties of Viburnum . Nature . 1966;212:837.  PubMed