Musannaf Ibn Abi Shayba 33:1332

Sa'id ibn 'Abd Allah narrated to us, from Nusayr, from Bakr, who said: When it was said to al-Rabi', "Will you not seek medical treatment?" he said: "I have desired that, then I remembered 'Ad and Thamud, the people of the Well, and many generations between them. So I realized that there were illnesses among them, and they had physicians, yet the one who treated and the one who was treated both died."