At home teeth whitening. What can I use to protect my gum against the whitening gel?

Vaseline is a good idea but Vitamin  E oil is better. You can find it at the pharmacy or at Walmart. Use a Qtip to apply it only to the gums before and more importantly after whitening. Are you using trays? Maybe they don't fit well or maybe you are using too much gel. You need a very small amount of gel only on the surface that touches the front of the teeth.

My suggestions are as follows:check what % gel you have first and foremost. Most people can easily tolerate the normal concentrations. But there are some stronger ones that some people just cannot use.only use a pea size amount of fell in each teeth space.***always wipe gently with a Kleenex in the vestibule...the area above where the tray ends, to wipe away excess gel.you can Vaseline your lips and the area above the teeth, not covered by the tray.skip days in between bleaching.only bleach for the recommended time..do not extend, or sleep with trays.  Sleeping with them is rarely recommended by most bleaching systems.**** most importantthis should help. I get very few if any complaints.

Vitamin E oil definitely works the best, but Vaseline will do. Use a Qtip to apply it right along the gumline as close to the teeth as possible but not on them before using your whitening trays. The best thing is to avaid getting the whitening solution on your gums in the first place. If whitening gel oozes out over the trays when you put them in , you are using way too much.If you are using stock trays, it would be good to check into getting custom made trays so you can better control where the whitening gel goes and you use less of it.