My son and I had problems with thrush every time he was put on an antibiotic. I read that taking a capsule of probiotics (live and active yogurt cultures) could help. I started giving it to my son and I. The next time he came down with thrush, the doctor recommended them! They're a bit spendy ($15 per bottle of 30). But every time we stopped giving them, he seemed to come down with another case of thrush (and me too!). The brand I use is Florajen 3 (recommended by doc. and websites about ridding thrush). You can find it at lots of natural foods and supplements stores around town. Whole Foods in St. Paul has it and so does the natural vitamins shop on Old Shakopee and Lyndale in Bloomington (in the strip mall with Festival). It needs to be refridgerated. I usually took 3 capsules a day when we had thrush, 1 per day as preventative if I didn't. For my son, I was told to open a capsule into a small containter. Then throughout the day (maybe 3+ times) wet your finger, put it in the powder, and put your finger in your baby's mouth for him/her to suck the powder off. My doctor said that the FDA hasn't approved it for use with infants yet, so there is no recommended dose; but it is just the cultures in yogurt, so I think perfectly safe. I gave my son about 1 capsule per day. This always seemed to clear it up within a few days.
Also, if you are having trouble getting rid of the thrush yourslef (wich could be passing back to you little one) you could have thrush in your ducts (wich a topical med. will not cure). Most docs don't know about this, but lactation consultants have the latest information. I contacted the LC at United Children's hospital in St. Paul and talked with them about it. They were willing to fax the information from their breastfeeding medical journal to my doctor so that an appropriate treatment could be given ( I think they give oral diflucan for an extended period of time so that it can clear your ducts of thrush).
Hope this helps. Also found this site to be helpful http://www.breastfeed-essentials.com/thrush.html. Best of luck getting rid of thrush. It is a tough on to get rid of (and painful in the meantime!).
:) M.