Bearberries are three species of dwarf shrubs in the genus Arctostaphylos. Unlike the other species of Arctostaphylos (see manzanita), they are adapted to Arctic and Subarctic climates, and have a circumpolar distribution in northern North America, Asia and Europe, one with a small highly disjunctive population in Central America. The plant contains arbutin, ursolic acid, tannic acid, gallic acid, some essential oil and resin, hydroquinones (mainly arbutin, up to 17%), tannins (up to 15%), phenolic glycosides and flavonoids. Bearberry appears to be relatively safe, although large doses may cause nausea, vomiting, fever, chills, severe back pain and tinnitus.