hi ,fi start to use crest 3d white with some crest ehitestrips treatment and i found after one week that i had some small pimple or bump and one big on my down lips it s natural?
Hello and thank you for your question. A tooth whitener which is generally HY Chat Doctor.  These products may cause an irritation or bumps on the outside of the mouth.  If this occurs you may have a sensitivity to the product.  Make sure that you don't have any lay on the surface of your skin and keep it on your teeth.  Pimples are products of bacterial infections in the pores of your skin.  Since these products do not contain pimple causing bacteria, it is unlikely that they would cause these issues.  Irritation, tooth sensitivity to cold, and gingival soreness and signs that too much has been used and have been in contact with other places other than your teeth.  Remember that tooth sensitivity caused by whitening agents is temporary and can be relieved with an anti-sensitive toothpaste.  Best regards