Black Ginger — Kaempferia parviflora — is called Krachai Dam in Thailand. Its rhizome has been used as folk medicine for many centuries. A number of pharmacological studies of Krachaidum had claimed benefits for various ailments. 

Black Ginger contains a number of powerful natural substances that increase Nitric Oxide in the blood vessels and that act as PDE-5 inhibitors which relax the smooth muscles in the blood vessels. Both these actions increase blood flow to the genital area to improve erectile function and therefore enhance sexual sensations and performance.