Nebulizer The pressurized air passes through the tube, turning the liquid medicine into a mist. During an asthma attack or a respiratory infection, the fog may be easier to inhale than the spray from a pocket inhaler. You can’t take deep breaths when your airways become narrow — like during an asthma attack. For this reason, a nebulizer is a more effective way to deliver the medication than an inhaler, which requires you to take a deep breath.