chlorhexidine buy at any pharmacy, it's in strong mouthwashes.
THIS!!
I was recently diagnosed with a slight geographic tongue. I went to the oral surgeon because my tongue was becoming irritated--certain food irritate geographic tongue. He gave me the prescription type--Chlorhexidine Gluconate 0.12% Oral Rinse, USP. Its very cheap, even if you don't have insurance. I used this for like a week or two, and it made my tongue A LOT better. I don't know how it will work for gums, but its good stuff!!