Acupressure [from Latin acus “needle” (see acuity) + pressure is an alternative medicine technique similar in principle to acupuncture. It is based on the concept of life energy which flows through “meridians” in the body. In treatment, physical pressure is applied to acupuncture points with the aim of clearing blockages in these meridians. Pressure may be applied by hand, by elbow, or with various devices. Some medical studies have suggested that acupressure may be effective at helping manage nausea and vomiting, for helping lower back pain, tension headaches, stomach ache, among other things, although such studies have been found to have a high likelihood of bias. Like many alternative medicines, it may benefit from a placebo effect.