Thrush

My son is on his second round of Nystatin for thrush. He doesn't have to finish the medication, just take it until it clears and then for two days after that. How do I know when it has cleared up? When I look at his tongue I cant really tell a difference and I never noticed any white patches in his mouth to begin with.

When I had thrush I never got the white spots my gums were really swollen and bright red

My son had that just a couple weeks ago and he had to take it for 9 days and by the 9th day it was gone. When it is completley gone there will be no white on his tongue or on the inside of his mouth. Our pedi told us that you wanna take it for at least 9 days because thrush is a slow growing bacteria.