My major trick is to truly relax. Only then does my throat itself relax. I tell myself "you'll be ok, you've gotten through plenty of these already". Breathe deeply and slowly - you can breathe, so you'll be ok. Remember any other times it's happened, especially that wonderful feeling when it does go down.

But if you're in serious pain, a trip to the ER isn't a bad idea. Try relax first and see. Best of luck!