STABBING PAIN
I'm using the 15% - my dentist dropped me down to 15 from 20 because I went back after the first night with stabbing pain in one of my teeth. Stabbing has not gone away (it's weird, I wear the trays overnight and am awakened by a stab around 7 or 8 am.) It recurs somewhat during the day randomly, and is also bad when the teeth are exposed to cold. I would stop using it, but my teeth are not whitening evenly - only the bottoms (part near the gumline is darker.)I skipped a night after doing it 2 nights in a row, but tried it again last night and this morning - STAB. (That was after taking 1/2 a Vicodin as a precaution, last night.)This is NOT WORTH IT. I have had 2 stabbing pains in the time it took me to write this.