How did you determine that this is a fungal infection? What was the initial appearance of the lesion? A ringworm infection does not ordinarily feel sore and ooze, but to help you I need also to know the color and consistency of the material that is oozing out of it.
For how often and over what period of time have you applied the neosporin cream?
Yes, I understand that a teenager is not likely to apply a cream consistently and regularly. It is not common for a fungal infection to ooze and form a crust. This sounds more like a skin infection caused by some common organisms in the environment. Your intuition to use an antibiotic cream is good, but I recommend that you clean the sore with half hydrogen peroxide and half tap water to remove the crust, then apply a thin layer of an triple antibiotic ointment 4-5 times a day. Because the lesion is behind the ear, it tends to stay moist and one wants to dry it up. If you still think it is a fungus that has become secondarily infected, it would not hurt or harm the condition by also using an antifungal cream 4-5 times a day. If it is a fungus, it may take two-three weeks of using the cream to get rid of it and keep it from recurring. It is wise to continue use of the antifungal for 4-5 days after it has cleared up, and the same for the antibiotic ointment.
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