Get an empty baby food jar & into it grate with a lemon-zest grater two or three large cloves (not bulbs) of garlic. Fill the jar with enough olive oil or flax oil to cover the garlic.
A couple times a day rub some of the oil onto the areas affected with a Q-tip. Leave on for a couple hours then apply your medicated shampoo to the area (no water, just the shampoo) leave on for about 15 minutes then wash off. Put a little hydrogen peroxide on it. Do this little regime for about two weeks and you should see a great improvement!