Musnad Abu Ya'la al-Mawsili 109:59

Ahmad ibn Mani' narrated to us, Muhammad ibn Yazid al-Wasiti narrated to us, from Mahmud ibn Ishaq, from Muhammad ibn al-Munkadir, from Jabir ibn Abdullah, who said: The Prophet (peace be upon him) said: "You must use antimony (ithmid) when sleeping, for it clears the vision and makes the hair grow."