Salicin safely be taken long-term at recommended doses. Higher than commonly recommended doses of this herb can cause stomach upset, nausea, or tinnitus (ringing in the ears). If any of these reactions develop. Stop taking the herb.
Avoid white willow bark, which can irritate the stomach, if you are sensitive to aspirin, or if you have an ulcer or other gastrointestinal disorder.
As with aspirin products, never give white willow bark to children or teenagers under age 16 with symptoms of the cold, the flu, or chicken pox. Although white willow bark is unlikely to cause the rare but potentially fatal condition called Reye’s syndrome in such cases—it is metabolized differently than aspirin—the similarity to aspirin is close enough to warrant caution.