Bee propolis (also known as "bee glue") is the resinous material used by bees to seal their hives. It consists of resins, pollen, and other materials gathered from the bark and leaf buds of various trees, combined with salivary secretions and wax provided by the bees. Propolis is usually brown or greenish-brown in color, with a pleasant honey or vanilla-like odor. Currently available as a dietary supplement, propolis has been used for a variety of medicinal purposes for several centuries.
Because propolis supplements are found in a variety of forms and potencies, dosage recommendations vary. Although propolis appears to have very low toxicity, with no adverse effects observed in mice at daily doses as high as 1400 mg per kg (2.2 lb) of body weight, severe allergic reactions have been reported in some individuals.