Is it swollen all over or only on one side? Any redness? How long has it been swollen and tender? Usually with fungus the nail keeps growing but just comes out unhealthy, yellow and brittle. There are a couple of chinese topical formulas that can be used for fungal infections but they are only to be swathed on the toes and nails, some fungal infections lie within the nail and need to be treated thru the bloodstream, so your only hope might be a western med that can accomplish that. Find a eastern pharmacy that carries Hua Tuo Gao, Tuijin Liniment, or Xiao Yan Tang Shang Cream, better yet go ahead and see a practicioner to assess your situation for the best outcome.

I have read that Vicks mentholated rub will kill toe nail fungus, but have never had call to try it myself. It is a bit of folk medicine, your mileage may vary, but just thought I would throw it out. Read about this on the people's pharmacy.