Introduction to the respiratory system and medications

The respiratory system exchanges oxygen (O(_2)) and carbon dioxide (CO(_2)) through two main processes:

• Inspiration (inhaling), which brings air into the lungs
• Expiration (exhaling), which moves air out of the lungs

It includes structures in the upper and lower respiratory tracts, such as the nose, trachea, bronchi, and lungs.

Asthma is a common respiratory disease caused by an abnormal allergic response. This response leads to inflammation and narrowing of the airways, which makes breathing more difficult. Several medication classes are used to treat asthma:

• Some are used as rescue medications for quick relief during an attack
• Others are used to prevent attacks and reduce their severity over time

Chronic obstructive pulmonary disease (COPD) includes chronic bronchitis and emphysema. These conditions cause long-term breathing problems.

An acute infection of the lung tissues is called pneumonia. Pneumonia is treated with antimicrobials tailored to the causative microorganism.

Table showing common drug classes and examples of the respiratory system