A flowering plant native to Malaysia, Thailand and other parts of Asia. It is an extremely bitter plant, traditionally used to treat irritated skin and as an antimicrobial agent.

Longifolia extract is sometimes used to treat erectile dysfunction, and supplement manufacturers frequently claim that the plant has testosterone-boosting abilities. However, there is limited clinical evidence for this use, and more research needs to be completed to establish whether longifolia is an effective sexual enhancement supplement.

The plant is considered safe, although some users may experience nausea and other relatively mild side effects.