Abbad bin Mansur narrated from 'Ikrimah who said:
"Ibn 'Abbas had three boys who were cuppers. He would use the proceeds from two of them for himself and his family, and one of them would cup him and his family." He said: " Ibn 'Abbas said: 'The Prophet ﷺ said: 'How excellent is the slave who cups, letting the blood, relieving the back, and clearing the vision." And he said: "Indeed the best for you to cup on are the seventeenth, the nineteenth, and the twenty-first." And he said: "Indeed the best of what you treat is As-Sa'ut, Al-Ladud, cupping and laxatives." And indeed, The Messenger of Allah ﷺ was given medicine by Al-Abbas and his companions. So the The Messenger of Allah ﷺ said: "Who gave me this medicine?" All of them were silent, so he said that there shall not remain anyone in the house but he should be treated with Ladud except for his uncle Al-Abbas.'" An-Nadr said: "Al-Ladud is Al-Wajur."