What is حجامة (wet cupping)?

Hijama (cupping) is the removal of stagnant, corrupted blood accumulated under the skin. It is among the remedies recommended in Islam. Prophetic hadiths have indicated its virtues, among them the Prophet, peace and blessings be upon him, said: "Healing is in three things: in a cupper’s scarification, or a drink of honey, or cauterization with fire, but I forbid my nation from cauterization." The Prophet, peace and blessings be upon him, was cupped, and the angels recommended it. The Companions were also cupped and recommended it. Cupping is advised on specific days of the month (17th, 19th, 21st), and it should be avoided on Wednesdays, Fridays, Saturdays, and Sundays, while it is recommended on Mondays and Tuesdays. Modern medicine has proven the multiple benefits of cupping for heart, blood, liver diseases, and more, and numerous works have been written about it. Ibn al-Qayyim al-Jawziyya mentioned the benefits of cupping on the kahil (upper back) and the akhda'ayn (two jugular veins) in treating headaches and their related parts.