My dentist recommended them to me and told me specifically not to use a double dose, because I asked the same question. Apparently it's damaging to your teeth, and simply doubling up would not actually speed up the whitening process.

It's less about sensitivity and more about the real process that occurs. I've been on it for about two weeks now and I've seen tremendous progress with whiteness, and I've done the recommended dose.

Enjoy your soon-to-be whiter teeth!

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