I've always self treated mine. I use the drug store corn removal lotion and after a few days just snip off the dry top. I use an antibiotic ointment after.
I was reading that other remedies include: vinegar wash, lemon wash, baking soda paste and terpentine oil. It was recommended that after the corn is softened to use pumice to remove the dead area.
Podiatrist told me NOT to use the stick on removal disc on the inside of the toes.