Musnad Ahmed: Hadith 3525

‘Ikrimah was asked about the one who is fasting - can he be treated with cupping? He said. It is only disliked because it weakens the individual. And he narrated from Ibn ‘Abbas (رضي الله عنه) that the Prophet (ﷺ) was treated with cupping when he was in ihram because of some poisoned mutton that he had eaten, that was poisoned by a woman from among the people of Khaibar.