Musannaf Ibn Abi Shayba 24:103

Mu'adh ibn Mu'adh narrated to us, he said: Ibn 'Awn narrated to us, he said: Ibrahim mentioned that [a messenger] was sent to him during the time of al-Mukhtar ibn Abi 'Ubayd. So he smeared his face with a coating and drank a medicine, and he did not come to them, so they left him.