My neck and upper back is so sensitive to the touch am I wondering how I would react to apply biofreeze and then Zostrix.

I know when I put Biofreeze like cream on my back before it made the burning pain worse even though it was a cooling feeling.

Also the instructions for the Zostrix cream says put a pea sized amount on the affected area. My area is large. Its half of teh back of my neck, both my sholder blades and sometimes triceps.

I am concerned about putting too much on.