I read that a while back. Laughed my ass off, mostly because I had a very similar experience with Dilettante Sugar Free Chocolate Cherries. (They sell them at Costco at Christmastime.) I thought I was going to die. It was not a very Christmas-y experience.
Reading the reviews is almost as addictive as the candy sounds to be.
And yes, if it’s the sugar substitute, then it could happen with any sugarless candy.