Glucagon-like peptide-1 (GLP-1) is an incretin hormone secreted in response to food intake that acts biologically by binding to GLP-1 receptors. The primary function of GLP-1 is to stimulate insulin secretion and inhibit glucagon secretion, which helps limit after-meal spikes in blood glucose. GLP-1 reduces intestinal contractility, slows down gastrointestinal motility and emptying, and also acts directly on the hypothalamus, thereby regulating appetite and food intake. Due to its metabolic effects, GLP-1 forms the basis of medications currently used to treat type 2 diabetes (T2DM) and obesity. However, it has also been observed that the use of GLP-1 agonists in the treatment of obesity or diabetes has a beneficial effect on comorbid respiratory conditions. This narrative review analyzes the scientific literature and describes the most recent information on the impact of GLP-1 receptor agonist (GLP-1 RA) therapies on the most common respiratory disorders-both the beneficial and undesirable effects. We discuss evidence that acute lung injury, COVID-19, pulmonary fibrosis, asthma, chronic obstructive pulmonary disease (COPD), and obstructive sleep apnea can benefit from therapies with various GLP-1 RAs. They can complement existing lung-targeted treatments, but as research progresses, they are likely to play an ever more important role in the treatment of respiratory diseases.
