Mold is a common asthma trigger, and it thrives in bathrooms and other high-moisture areas. Good ventilation is essential. Use the bathroom fan every time you bathe or shower to help remove the moisture that mold needs to thrive.
Also try using a squeegee on the bathroom tiles. It takes about 30 seconds, wipes off extra moisture, and is a terrific strategy for preventing mold, says Dr. Plaut.