I don't think it would be able to penetrate the skin long or far enough by it's self, Griz. I had a fungus get under my skin like that, and finally got rid of it by using Terrasil (sp?) a silver ointment that didn't come off easily and penetrated the skin because one ingredient was jojoba oil.
I'm not using it any more--the infection's gone, but the last jar I had was too weak until I added some silver nitrate powder. I'm quite sure it got bought out by the pharmaceutical cartel, so they probably have made it so weak by now it barely works.
But just add your own silver (it is kinda pricey) and the texture should still be good enough to keep the ointment on the affected skin. It does stain, so maybe a gauze patch so you don't ruin all your socks.
Of course this post is 8 years old--I hope they've got it fixed by now!