
Q. I was interested in the letter from a reader who applied tincture of iodine to his nails to fight fungus. He mentioned that it stains the nails brown. I am surprised you did not tell him that iodine also comes as a colorless liquid. My mother used it for years to control toenail fungus.
A. Many other readers hastened to tell us that we should have mentioned clear iodine. It is also called decolorized or “white” iodine (yodo blanco in Spanish) and won’t stain the skin the way brown tincture of iodine does. It should be available in most drugstores, though you may have to ask the pharmacist to help you find it. Iodine is a good disinfectant and also has antifungal activity.