Whether treating a fungal infection in the feet or the nails, you really need to be treating three things:
1- Your feet
2- Your nails
3- Your shoes
Most doctors will tell you how to treat your foot fungus and your nail fungus, but keep in mind that the fungus that causes athletes foot or nail fungus lives everywhere and on almost any surface (just like the fungus that causes mold/mildew in your homes). As a result, you are constantly exposing your feet to the fungus unless you take steps to reduce your exposure.
First, avoid going barefoot in public areas or on hard surfaces where moisture abounds. Public pools, gym locker rooms, showers and bathrooms are havens fungi. There is a goood chance this is what causes your foot or nail fungus. When in public make sure to wear either a flip flop or a shower shoe at all times. Cleans the feet with soap and water and dry them thoroughly especially in between the toes.
Second, treat your shoes. Remember, fungus can live in the fabric of your shoes so once you have an infection in your feet, they have already set up shop in your shoes. They make several non toxic sprays that you need to use in ALL your shoes regularly. Also, allow your shoes to air dry whenever possible in the sun if you can.
Third, check to see if your feet sweat alot. If they do, they make several anti-perspirants designed to control excessive foot sweat. Buy a 10 pack of cotton socks and change them throughout the day.