Abdur Rahman bin Nu’man Abu Nu’man Ansari narrated that my father narrated from my grandfather that my grandfather was brought to the Prophet Muhammad (peace be upon him). The Messenger of Allah (peace be upon him) passed his hand over his head and said:“If you are fasting, do not apply kohl during the day, but apply ithmid kohl at night, for it sharpens the eyesight and promotes hair growth.”Imam Darimi (may Allah have mercy on him) said: I do not see any harm in applying kohl while fasting.