How long does luekocytoclastic vasculitis take to heal?

It depends on cause: Leukocytoclastic vasculitis is typically a raised bumpy purple rash on the lower legs and feet ("palpable purpura") and clears up with treatment (usually prednisone) in a few weeks. This type of rash is sometimes caused by medications, infection, abnormal proteins in the blood, etc, so the length of time needed for the rash to resolve depends on the underlying cause.

It depends: It depends on the underlying causes. This issue can be seen with allergic reactions, infections and cancers.