I got here late, so this is for next time: Ricola cough drops...there's now lots of different flavors. Honey, lemon, whiskey, also a good combo. Straight honey on a spoon. I once had a recipe for this cough syrup, but I can't recall the measurements...it was whiskey, lemon, and vegetable oil...I'd err on the side of the liquor...or have a bathroom nearby. Blackberry brandy. If you try all of the above on the same night, I don't think you'll make to the gig, let alone through it. Hope you feel better.