Most people absorb such a small amount of Splenda that it would be near impossible for it to cause symptoms apart from indigestion associated with all non-digestable foods. However, I've had lockjaw and a stress headache (I'm assuming from the tight jaw muscles) nearly every time I use Splenda. I'm trying not to blame it, but it is the only consistant in my diet/behavior with the reaction.
Never had or heard of that problem with Splenda. I use it in everything from cooking to baking etc. ,,,,,,,,,,,,,,,,,,it's the BEST sweetener out there without the after taste. :–} :—)