It is narrated from Sayyiduna Ali bin Abi Talib (may Allah be pleased with him), the Messenger of Allah (peace and blessings be upon him) said: "You must use ithmid kohl regularly, it grows hair, removes particles or specks that enter the eye, and cleanses the eye."
Hadith Referenceسلسله احاديث صحيحه / الطب والعيادة / 1651