Sometimes the fluctuation in sensitivity is related to stress. Tags, socks and clothes bothered my son much more in the last couple of weeks with the transition back to school. Jeans that he tried on at the store and LIKED while there are sitting unworn in the drawer - he continues to wear his old wornout jeans from last school year because the new ones "don't feel right." I'm just waiting patiently until the day he decides to try them because sooner or later he will be able to handle the "new" feeling. We had to cut tags out of shirts that he's worn for months now *with* the tags but all of a sudden they bother him.
We try to just ride the tide and let take it all in a matter-of-fact sort of way. I'm encouraging MrWiggly to take more control over his own sensitivities by being more independent to "fix" the problem. So I just say that I'm sorry he's bothered by the socks and suggest that he either change to another pair, take them off and try again with the same pair or go without out. He actually seems to do much better when I support him problem solving these issues on his own. I think the sense of control over the hypersensitivity should be comforting to someone who feels like he's the victim of noxious stimuli.
You can try also to address the stress issues that might be underlying the new onset of hypersensitivity. BTW, I find this to be true whether there is a diagnosed SID or overexciteabilities - they look the same in some cases.
