The only way to be sure that it really is a fungus is to have a doctor take a sample...and grow it..GROSSS
I think we all know when something ain't right with the toenails though.
There are medications you can get from your doctor that you take internally..these can be hard on the bod. There are topical treatments as well. Then there are the natural remedies. Here is an interesting site I found..check it out... http://askwaltstollmd.com/fungus.html