This depends on the severity of the lowering of the ceiling pitch. Generally, however, careful strategy concerning amount and manner of voice use during this time will allow the mucosa to recover while you continue to work or perform.If for some reason you are under contract and must perform, it becomes a matter of strategy:All the basics of hydration, etc.Rest as possible,Remove the throat-killer song from the gigOverarticulateMake optimal use of amplification.In short, hobble through, knowing that you are swollen and making every possible choice to allow swelling to resolve. In a pinch such as when reviewers are attending, or it is a critical audition, a brief course of steroids, although we try very hard not to use them except in exceptional circumstances.