The betel (Piper betle) is the leaf of a vine belonging to the Piperaceae family, which includes pepper and kava. It is valued both as a mild stimulant and for its medicinal properties. Betel leaf is mostly consumed in Asia, and elsewhere in the world by some Asian emigrants, as betel quid or in paan, with or without tobacco, in an addictive psychostimulating and euphoria-inducing formulation with adverse health effects. Betel is notable for staining the teeth of regular users.