The bark and root bark of this plant are still used to make medicine. As the name suggests, cramp bark is used for relieving cramps, including muscle spasms, menstrual cramps, and cramps during pregnancy. Cramp bark is also used as a kidney stimulant for urinary conditions that involve pain or spasms.
Cramp bark (Viburnum opulus) also known as guelder rose, highbush cranberry, and snowball tree is a tall, flowering shrub with red berries and clusters of white flowers.
Native to Europe, it also grows well in the United States and Canada.
An herbal supplement made from the shrub s dried bark has traditionally been used to treat pain from muscle cramps, especially period cramps, although other parts of the plant may also offer benefits.