Cramp Bark

Cramp bark is the dried bark of Viburnum opulus, the guelder rose, a deciduous shrub of Europe, northern Asia and North America, harvested from the stems and branches in spring. Nustras supplies it as dried cut bark and milled powder, with extract powders on request. The bark contains tannins, coumarins including scopoletin, the bitter principle viburnin and small amounts of salicin.

Cramp bark is formulated into botanical supplements in capsule, tablet and liquid form, herbal tea blends, tinctures and fluid extracts, and multi-herb formulas of the women's-care category, often alongside black haw.

Supplied as greyish-brown cut bark with a paler inner surface, or a light brown powder with a faint odour and an astringent, bitter taste. Botanical identity is confirmed by macroscopic examination and thin-layer chromatography; cut size, moisture and ash are standardised to specification. Heavy-metal, pesticide and microbial limits are supplied to specification and confirmed on each lot's certificate of analysis.

Nustras supplies cramp bark in bulk commercial quantities, in food-grade bags and fibre drums, to manufacturers and formulators internationally, with a certificate of analysis, specification sheet and country-of-origin documentation on every lot. Cramp bark is an accepted botanical ingredient in major supplement markets; buyers confirm the plant part, preparation and permitted claim for their application. Contact us for grade, pricing per kilogram and lead time.