<P>I use acidophilus frequently. I have found, through research, that the only way to get any real benefit from acidophilus is to make sure that it is enteric-coated capsules (so it survives the stomach acids - the bacteria are very fragile) in a light blocking container (like opaque glass or plastic) that has been kept in a refridgerator from storage to use. Don't buy a brand that keeps their product on a shelf because it is too warm and the bacteria will die off. Yogurt is good, but even the kind that has live cultures has very little. It is refridgerated, which is good, but during the processing, all the bacteria are removed (pasteurization) and then the acidophilus has to be added back in. By the time you get it at the store, most of the bacteria are dead because they have used up all the sugars in the yogurt and run out of food, so they die off. There may be only a few left. So, not to say don't use yogurt, but it's probably not enough in itself to really help you. HSO - homeostatic soil organisms are heartier than acidohpilus and they work great together. Acidophilus builds colonies that live in your gut and help keeo a balance. HSO are transient (they don't build colonies, they just do their job and die off), but they survive the stomach acids well. HSO works by feeding off the stuff that yeast usually feeds on so that the yeast has less opportunity to grow. Think also about topical things, nystatin is ok, but it doesn't cure yeast, it just relieves symptoms. Try calendula (in many diaper ointments - I like Earth Friendly Baby). You can put a few drops of tea tree oil in a bath. If you get thrush (which is why your mouth hurts, Dea) you can open up the acidophilus capsules and coat your mouth with it. Nystatin washes help relieve the pain. I usually try to start a combination of these things ahead of time if I anticipate being put on antibiotics and then make sure to continue a couple of weeks after I have finished the antibiotics. My website (<A href="http://www.geocities.com/murrensnaturemama/wellness">www.geocities.com/murrensnaturemama/wellness</A>) contains much of this information in greater detail if you are interested. </P>