Thanks to all those who responded to both of my questions. I appreciate your advice. However, I am sorry to say that as for the advice you offered about using Retainer Brite orally, I did not listen. Against your advice, the instructions on the box, and my own better judgment, I put the tablet in my mouth. Even worse, I did it during class. Toward the middle of my biology class, I got kind of bored, and in addition my breath started to smell bad, so I looked down at my Retainer Brite (it was in my backpack) and decided to give it a shot. I figured since it was peppermint it would make my breath smell good, and I didn't notice the part about foaming on the box.
Anyway, about 20 seconds after I popped it in, I realized it was a very bad idea. I didn't want to swallow it, because it tasted horrible, and I thought it might make me sick, so I just kept it in. I'm seated next to the wall in class and my lab partner, Zack, sits right next to me, so I was kind of blocked in. I didn't know what I was going to do. I couldn't tell Zack to move because I couldn't open my mouth or all the foam would spill out, so I just kept sitting there, hoping it would go away. In the meantime I tried to act normally so no one else would notice. It was working pretty well. Everyone was focused on the professor, that is until he started asking questions about our assignment, and he asked me to describe the difference between eucaryotes and procaryotes (sp?). I still couldn't bring myself to swallow in fear of throwing up, so at first I hoped if I ignored him, he would go to someone else, but instead he just asked me again. I looked at him, then did the only thing I could. I opened my mouth with blue foam spilling out all over the desk and said "I think I'm gonna be sick!" Girls started gasping, guys started moving out of the way, and I couldn't be sure but I think Zack was nearly sick himself. He stood up out of his chair and walked (or more accurately, ran) midway across the classroom as I sprinted for the bathroom and rid myself of the putrid blue slime that was gushing from my orifice. It totally turned my mouth and teeth blue and did nothing for my breath (you can't really notice the peppermint taste apart from all the chemicals). I couldn't bring msyelf back to class to get my stuff until after it was over, so now I'm behind in my notes, humiliated in front of my class, and I can't seem to get the taste of potassium out of my mouth.
I wrote this to hopefully discourage anyone else from trying this, and to see if maybe anyone else could tell me something more embarassing that they did so I can feel a little better.
Thanks everyone, and from now on I'll try to listen to the advice you give.
Feeling blue, and not just in my mouth,