Why Is Hhsone Cream Prescribed For A Toddler With Urinary Pain At The Penis?

Hello doctor!! My 3.8 yr old son was complaining of a little pain in the time of passing urine from last few days.we took him to doctor. Doctor prescribed an ointment(HHSONE CREAM) to be applied in his penis for 2 months . Is it something very serious?? Can i get some help please. Thanks