Iolite
If the infection is below the skin (cellulitis) then using a drawing salve (like ichthammol with a few drops of oregano oil (if it burns a little when applying then you've got enough organo oil) mixed in and cover with a bandage. The icthammol will help draw the infection to the surface and the oregano oil will help bring heat to help draw it out and be anti-infective. Reapply a new bandage with salve daily.
I've used this on several skin infections successfully, including my daughter's infected thumb (initially caused by a torn hangnail). Her thumb became red, swollen and throbbing. I had her soak it in warm salt water with a few drops of oregano oil in it (I didn't have enough CS at the time to put in the soak) and then I mixed up some ichthammol and oregano oil and applied all over the thumb cuticle line and wrapped up in a bandage. By the next morning, it no longer throbbed. It worked so well that she routinely asks for the stuff. I now have a small batch mixed up and ready in the bandaid box. The most recent time I used it was last week on an infected blister on her heal. I had her soak her foot in warm salt water with a cup of CS and then after her soak applied the salve with a bandage and sent her to bed. The next morning she said it didn't hurt so much. We applied a fresh dressing with the salve and repeated it that night after bath and by the 3rd day, the infection was gone and the wound was healing nicely.
You can get the 20% icthammol ointment at drugstores (call around, independently owned pharmacies and Walgreens are your best bet) or online. After paying up to $6 for a 1oz tube, I finally bought 14oz for $7 at a equine supply site online. That stuff should last me for years!