Plastic suction cups on the skin and creating a vacuum, negative pressure, by suctioning out the air.  The purpose of cupping is to enhance circulation, help relieve pain, remove heat and pull out toxins and stagnation that linger in your body's tissues. Cupping causes the skin to temporarily turn red, blue or purple, especially if there is an injury, energetic blockage, or stagnation under the area that was cupped. The skin discoloration can last anywhere from a few days to a couple of weeks but is rarely painful. The next day a person might feel very tired or drained. Cupping is detoxifying and requires a person to keep the cupped area out of sun and wind. It is important to also hydrate with water and electrolytes after because dehydration and low energy the next day can occur.