Campho-Phenique Antiseptic Liquid is my 24hour treatment for mouth ulcers. Dab on a canker sore with q-tip soaked in campho-phenique. Put the Q-tip against the mouth ulcer for one minute. Then remove Q-tip and rinse mouth out with water. This has worked for me every time since the 1970's when it was shown to me.
Active Ingredients: per container: Camphorated Phenol (Camphor 10.8%, Phenol 4.7%) (Pain reliever/antiseptic) Inactive Ingredients: Colloidal Silicon Dioxide, Eucalyptus Globulus (Eucalyptus), Glycerin, Light Mineral Oil.
Camphor Spirit for Canker Sores
Camphor spirit (not campho phenique) will remove them. Dip a Q tip in the solution & hold against the sore...it stings but after a couple of treatments it should disappear.