The infection has healed with postinflammatory hyperpigmentation
. Usually with time pigmentation lightens but to hasten its clearance you can apply the combination suggested by your doctor. The time taken for clearance or reduction in pigmentation varies from person to person. It depends on one's skin type, depth of infection and inflammation. So duration required for clearance would be difficult to predict . However, I can reassure that with the medicine prescribed , it would reduce.
Hope that answers your query.