The air inside the cup is heated and the rim is then applied to the skin, forming an airtight seal. As the air inside the cup cools, it contracts, forming a partial vacuum and enabling the cup to suck the skin, pulling in soft tissue, and drawing blood to that area. Alternately, the suction is created by a hand-pump and blood is allowed to collect. According to the American Cancer Society, "[a]vailable scientific evidence does not support cupping as a cure for cancer or any other disease ".
Broadly speaking there are two types of cupping: dry cupping and bleeding or wet cupping (controlled medicinal bleeding) with wet cupping being more common. The British Cupping Society (BCS), an organisation promoting the practice, teaches both. As a general rule, wet cupping provides a more "curative-treatment approach" to patient management whereas dry cupping appeals more to a "therapeutic and relaxation approach". Preference varies with practitioners and cultures
The cupping procedure commonly involves creating a small area of low air pressure next to the skin. However, there is variety in the tools used, the method of creating the low pressure, and the procedures followed during the treatment.
The cups can be various shapes including balls or bells, and may range in size from 1 to 3 inches (25 to 76 mm) across the opening. Plastic and glass are the most common materials used today, replacing the horn, pottery, bronze and bamboo cups used in earlier times. The low air pressure required may be created by heating the cup or the air inside it with an open flame or a bath in hot scented oils, then placing it against the skin. As the air inside the cup cools, it contracts and draws the skin slightly inside. More recently, vacuum can be created with a mechanical suction pump acting through a valve located at the top of the cup. Rubber cups are also available that squeeze the air out and adapt to uneven or bony surfaces]
In practice, cups are normally used only on softer tissue that can form a good seal with the edge of the cup. They may be used singly or with many to cover a larger area. They may be used by themselves or placed over an acupuncture needle. Skin may be lubricated, allowing the cup to move across the skin slowly.
Depending on the specific treatment, skin marking is common after the cups are removed. This may be a simple red ring that disappears quickly, the discolouration left by the cups are normally from toxins penetrating the skin, coming from inside out as a form of fluid film, and vapour left in the cups. It is possible more aggressive treatments can result in bruising especially such as dragging the cups while suctioned from one place to another to break down muscle fiber. Usually treatments are not painful, but treatment is discontinued if the subject experiences more than minor discomfort
Wet Cupping (Al-Hijamah or medicinal bleeding)
Further information: Hijama
While the history of wet cupping may date back thousands of years, the first documented uses are found in the teachings of Prophet Muhammad . According to Muhammad al-Bukhari, Muslim ibn al-Hajjaj Nishapuri and Ahmad ibn Hanbal, Muhammad approved of the Hijama (cupping) treatment.
In this alternative form of bloodletting or medicinal bleeding, also called blood cupping, a small scratch or incision is made with a lancet prior to the cupping, and the pressure difference extracts blood from the skin. Islamic traditional medicine uses this technique – called in Arabic Al-Hijamah or Hijamah - with a number of hadith supporting its recommendation and use by the Islamic prophet Muhammad. As a result, the practice of cupping therapy has survived in Muslim countries.
Alternatively, mild suction is created using a cup and a pump (or heat suction) on the selected area and left for about three minutes. The cup is then removed and small superficial skin incisions are made using a cupping scalpel. A second suction is used to carefully draw out a small quantity of blood. The procedure was piloted and developed by Ullah et al 2005 and has been endorsed by the British Cupping Society which aims to promote, protect and develop professional standards in cupping therapy.