Willow bark is the original source of aspirin. Traditionally willow bark has been used in the same way as aspirin, to reduce pain and fever. The Bayer company discovered a chemical process that improved the tolerance of synthetic salicylic acid (a related active component of willow bark), and modern-day aspirin was born. Our Willow bark extract is purified to contain 98% salicin, the naturally occurring active component.
Willow Bark in the treatment of low-back pain:
http://www.sciencedirect.com/science/article/pii/S0002934300004423
