3 drops of eucalyptus oil in a cup of hot water. Cover with a lid. Inhale vapor into throat. It will sooth the throat beyond anything you've ever tried for hoarse throat.
Don't use your voice between gigs, drink room temp water, no sodas, whiskey, beer, wine, or acidic beverages. I guarantee the eucalyptus oil vapor. For congestion black pepper in chicken broth, thai food, ect. are all natural decongestants.

Peace on and offshore,
Scotty Lee