Acupuncture is an ancient Chinese medical system that accesses and balances the body's vital energy (Qi, pronounced chi) via acupuncture points, which are located along the meridians (energy channels) of the body. The acupuncture points can be used with either pressure (acupressure) or very fine needles (acupuncture). Acupuncture also increases blood flow, decreases blood pressure and increases the production of pain-killing chemicals called endorphins. The immune system can also be stimulated using acupuncture.