The sprays for asthma relief are divided into two main categories: first, single drugs; second, combination drugs. Single drugs are glucocorticoids or short-acting beta2 agonists, such as fluticasone propionate inhalation aerosol, salbutamol inhalation aerosol, terbutaline inhalation aerosol. Salbutamol inhalation aerosol is effective during acute asthma attacks and relieves airway hyperresponsiveness within seconds of inhalation. The compounded drugs are budesonide formoterol powder inhaler and salmeterol tetrasone powder inhaler, which are a mixture of long-acting beta2 agonists and long-acting glucocorticoids. For patients with asthma who have failed to be treated with single glucocorticoids or the application of bronchodilators, a combination of both drugs is required.