Looking for some remedies

AB

Couple months ago my husband got something on his forehead and became infected. He thinks it’s from wearing his new hat that he got . It must have made his forehead itchy so he scratched it and it went down Hill from there . It got so red, inflamed and angry looking. Went to his doc and they gave him antibiotics. It got better but it has been almost two months and that thing on his forehead still hasn’t completely closed and healed. Anyone know any remedies to treat this? I think right now it just need to close.