kmeb,

I have had the same reaction; heart racing that is and I only use half a patch when I feel it might be helpful. And it doesn't happen all the time...just every now and then. I used to cut up one or even two to place on my neck. But found they really weren't all that helpful for my neck. They did take the edge off the lumbar pain but not too much. I much prefer the injections even though I can have the jitters for a couple of days...but that goes away. At least injections don't make my heart race like the Lidoderm can and again, it isn't all the time...just every once in awhile. But when it happens, I rip that thing off.