Which of the following is a type of respiratory drug?

Bronchodilators are a specific class of respiratory drugs that work by relaxing the muscles around the airways, leading to their dilation. This allows for improved airflow and is particularly useful in managing conditions such as asthma and chronic obstructive pulmonary disease (COPD). Bronchodilators are essential in treating acute respiratory distress and facilitating breathing in patients with constricted airways.

In contrast, antihistamines primarily alleviate allergy symptoms by blocking histamine receptors and are not specifically targeted for improving respiratory function. NSAIDs (non-steroidal anti-inflammatory drugs) are used to relieve pain, reduce inflammation, and lower fevers but do not directly affect respiratory pathways. Anxiolytics are medications that reduce anxiety, and while they may have secondary effects on breathing rates, they are not classified as respiratory drugs aimed at treating respiratory conditions. Therefore, bronchodilators distinctly stand out as medications that directly impact respiratory function and airway management.