The antibiotics alone will predispose you thrush, the steroid in the
Symbicort will also . Do you rinse your mouth after each
use? I find that if I don't do this, I too get thrush. Simply rinsing my mouth after each use prevents the yeast from coming back.
Taking probiotics because you are on antibiotics isn't a bad idea either, or eating yogurt with active cultures.
Also, are you able to just leave a message with your doctor and have the medicine called in to the pharmacy?