How long do you leave toothpaste on when putting it on a pimple?

I%26#039;ve decided to try this method out. I heard it dries your skin out very much, but I am willing to take my chances - though some people say don%26#039;t leave it on all night otherwise it will dry your skin way too much. How long would you suggest leaving it on?|||I leave it on overnight ONLY on the trouble spot|||A few minutes will help. Beyond that the toothpaste starts to dry and it can%26#039;t do much when dry.|||I did mine overnight.|||do it overnight