While the only reason an inflamed throat should affect your voice is because it reduces the size of the pipe between your vocal cords and your palette - you SHOULDN'T be depending on the back of your throat at all, unless it's roughen up the odd dramatic stress note - an old remedy is to slice up an onion in a bowl, cover it in brown sugar, cover the lot with a damp cloth and/or leave in the fridge over night. In the morning, drink the resultant syrup. It doesn't taste as bad as it sounds, and it works.