What will clear darkened skin previously infected by fungus; i.E. Jock's itch?

Hydroquinone. Hydroquinone is the gold standard for fading dark marks. It is available in over the counter preparations at a 2% strength or prescriptions can be given for stronger strengths. Test it on a small area for a few days before using on larger areas to ensure you are not allergic. Discontinue if redness, peeling, or dryness develops. Be sure that the jock itch is well controlled before fading.