How do people get yeast infections? i always am getting one. my ob just gives me an antibiotic what can i do... am i allergic to something?

Antibiotics & yeast: Antibiotics are a known cause of vaginal yeast infections by killing all of the "good bacteria" in the vagina and changing the pH to allow yeast to proliferate. A yeast infection should be treated with a anti-fungal agent and not an antibiotic.

Yeast infections: Most women will get a vaginal yeast infection at some time. Candida albicans is a common type of fungus. It is often found in small amounts in the vagina, mouth, digestive tract, and on the skin. Most of the time, it does not cause infection or symptoms. Candida and the many other germs that normally live in the vagina keep each other in balance. However, sometimes the number of Candida increases,

Antibiotic induced: IT IS NOT UNCOMMON TO GET YEAST INFECTION DURING USE OF ANTIBIOTICS. Since it kills good and pathogenic bacteria, and promotes yeast infection. Consuming high quality greek yogurt helps decrease such infections. Probiotics help too.