Dermatology Questions? Ask an Online Dermatologist.
Hi Dr Ashori here, give me a moment to reply please.
If you have a picture that would be helpful, you can upload it here.
However, I already know what's going on and thankfully what you have is reversible.
It's a form of angular cheilitis (not actual AC). The fact that it healed is a good sign, however what can happen is because of the bacteria found in the mouth the skin can get thickened, scaly and dark. This is common after such an injury/infection.
It's important to know what caused it, either a cold sore, allergic reaction or perhaps a cold that you recently had.
In either case, the issue now is a cosmetic one and in order to make it heal you need to do a few things, please follow everything on this list:
Do these things first, then you have to wait 2-3 weeks for all the dead skin to disappear. After that the new skin that grows will be healthy normal skin and the dark patches will go away.
If by chance there is a still a little bit of darkness you can always try something like Tri-Luma cream or you can use the non-prescription version called Hydroquinone which should be applied for no more than a month or it can make the darkness worse.
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