White willow bark can be very effective for relieving headaches, as well as acute muscle aches and pains.It can also alleviate all sorts of chronic pain, including back and neck pain.When recommended for arthritis, especially if there is pain in the back, knees, and hips, it can reduce swelling and inflammation and increase joint mobility.In addition, it may help ease the pain of menstrual cramps - the salicin interferes with the action of hormonelike chemicals called prostaglandins that can contribute to inflammation and cause pain.