Patient Question - Should I be on Lamisil for over 3 months?

I had a patient ask me today if they should have 2nd course of the oral Lamisil.  They had just taken it for 3 months and have noticed great results on their nails and would like another prescriptions.  This is not necessary much of the time because the medication remains in the blood stream for a longer period of time than the 3 month course of the medication.  It should continue to work even though you are not taking the medication.