I had small spots under my chin where the neck starts. I ignored it and then it got a bit scratchy, and still ignored it. After a few weeks I saw that thee were two round spots with prickly outer edge. I knew it was ring worm. I first used cortaid from CVS, did not work, the ring got bigger. Now shaving became harder. I tried hydrogen peroxide. It did not budge. Finally I mixed 17% H2O2 (Hydrogen-Peroxid) and 3% store brand H2O2 (Hydrogen-Peroxid) in 1:3 ratio. I applied that solution of H2O2 (Hydrogen-Peroxid) three four times a day. Now in one week the ring worm is almost gone. Also it has stop spreading elsewhere, which I had noticed on my chin another small one appearing.