Willow bark eases inflammation which wil also ease aches and pains. The chemical salacin which is similar to the salicylic acid in aspirin is found in the bark of the white willow. White willow comes as a dried herb that can be brewed like tea, or it comes as a capsule or liquid supplement. Because the chemical property in willow bark is so similar to aspirin, you should not take it if you have sensitivity to aspirin or if you are taking a blood thinner. You should use willow bark with caution if you are also taking over the counter anti-inflammatory drugs such as ibuprofen or naproxen.