Question: What is the ruling on using a cream or penicillin (ointment) on wounds – does it break (the fast) or not?


Answer: “As for using cream and penicillin (oilment) on wounds, it does not harm  (a person’s fast) because it does not get inside the belly (or abdomen)”.

[Fath Ar-Rabb Al-Wadood Fil Fataawaa War-Rasaa’il War-Rudood’ by Al-Allaamah Ahmad Bin Yahyah An-Najmi (rahimahullaah) 1/324]