Penicillin skin ointment is a topical medication containing penicillin, an antibiotic that is used to treat bacterial infections of the skin. It is typically applied directly to the affected area of the skin and helps to eliminate the bacteria causing the infection.It is important to follow the instructions provided by your healthcare provider or the manufacturer when using this ointment. Make sure to clean and dry the affected area before applying the ointment, and wash your hands thoroughly after applying it to avoid spreading the infection.If you experience any severe or persistent side effects while using this medication, contact your healthcare provider immediately. It is also important to finish the full course of treatment, even if your symptoms improve before the medication is gone, to ensure that the infection is completely eliminated.