Prickly Ash (Zanthoxylum americanum) is a deciduous shrub or small tree in the Rutaceae family native to Eastern and central North America. It is a thorny aromatic shrub with pinnate leaves, small fruits, and bark known for its tingling numbing quality. The bark and berries are the parts most often used in traditional preparations.

Prickly ash has long been used in North American herbal traditions as a stimulating bark and berry herb. It appears in older digestive, circulatory, and toothache-related formulas, often in tinctures or bark decoctions.

The plant’s distinctive numbing sensation is one of its best-known characteristics in traditional herb use.