Musnad Abu Ya'la al-Mawsili 232:3

Abu Khaythama narrated to us, Affan bin Muslim narrated to us, Abd al-Wahid bin Ziyad narrated to us, Uthman bin Hakim narrated to us, he said: Abu Bakr bin Muhammad bin Amr bin Hazm narrated to me, he said: The ruqyah (incantation) for the sting of a snake was presented to the Prophet, may Allah bless him and grant him peace, and he authorized it.