And from him, from Ali ibn al-Numan, from Said al-Araj, who said:
I (narrator) asked Abu Abdillah عليه السلام, peace be upon him, about ‘the fasting person undergoing cupping (al-hijamah).’ Imam عليه السلام said: “There is no harm, except if he fears weakness for himself.” – meaning which makes him unable to keep the fast.
Ali Akbar al-Ghaffari
Tahdhīb al-Aḥkām fī Sharḥ al-Muqniʿah, vol. 4, p. 330