Cupping is an ancient art found in many cultures to relieve pain. In fact, as early as the fourth century, the noted herbalist Ge Hong wrote about cupping in A Handbook of Prescriptions. Stagnation in the body is removed by bringing toxins to the surface to be released through the open pores. The increased blood flow into the area of cupping also allows the area to heal more quickly. Cupping has been found to affect the body up to four inches into the tissues, causing these tissues to release toxins, activate the lymphatic system, clear colon blockages, and help activate and clear the veins, arteries, and capillaries. Cupping is also used to treat respiratory conditions such as bronchitis, asthma, and congestion; as well as arthritis; gastrointestinal disorders; and pain. It is also used to treat depression. Fleshy sites on the body, such as the back and stomach are the preferred sites for treatment. Cupping can cause some swelling and bruises on the skin. As the skin is pulled into the cup, the blood vessels at the surface of the skin expand which may result in small, circular bruises on the areas where the cups were applied. These bruises are usually painless, however, and disappear within a few days of treatment. Patients with inflamed or broken skin; cases of high fever or convulsions; and patients who bleed easily are not suitable candidates for cupping. Pregnant women should not have cupping on their stomach or lower back.