My little guy is now 2 1/2 months old. He's had thrush since he's been about 4 days old. We cannot seem to get rid of it. We've tried nystatin, diflucan and gentian violet. The nystatin did nothing so we went on 4 weeks of diflucan. In that 4 weeks he got rid of it for a day and then it came back. Next we tried gentian violet which worked but then three days later it came back.