How to take Symbicort. Symbicort is not a rescue medicine. It will not work fast enough to treat an asthma attack or COPD flare-up. Your doctor may prescribe a fast-acting inhalation medicine to treat a bronchospasm attack. Always rinse out your mouth with water after using the inhaler device, to help prevent thrush (a fungal infection in the mouth or throat). Do not allow a young child to use this medicine without help from an adult. While using Symbicort, your doctor may need to check your vision and bone mineral density.