A blue inhaler is commonly used for asthma and other respiratory conditions. It's often referred to as a "reliever" inhaler because it provides quick relief from asthma symptoms like wheezing, coughing, shortness of breath, and chest tightness.

The most common medication in a blue asthma inhaler is salbutamol (also known as albuterol in some countries), which is a short-acting beta-agonist (SABA). This medication works by relaxing the muscles in the airways, making it easier to breathe. Blue inhalers are typically used on an as-needed basis, meaning they are used when symptoms arise rather than on a regular schedule.