What are some good home remedies for a canker sore?

Gargle salt and water, put some of that orajel on it

I would try Tee Tree oil…tastes like crap. But I would raid the piggy bank and buy Kanka Works like a charm.

I apply a wet and warm paper towel.

I had my mind focused on golf when I answered….it is Tea Tree Oil!

Any over the counter ointment from the pharmacist works if you make sure that you dry the sore first of all so that the ointment can stick to it. Dab the ointment on the exact spot, don’t smear – once it touches your mouth, it can’t really be moved.

The sore is caused by your saliva attacking the open wound. It’s just doing its job. But by placing a barrier between the sore and the saliva, your body can get to healing it.

Painful business. You have my sympathy

The topical ointments suggested above do work but tend to rub off fairly quickly during the day. My go-to cure is gargling with warm salt water several times a day and at bedtime. I sometimes add a tiny bit of hydrogen peroxide to the water if the sore is really bad.