Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are a class of medications used to treat and manage type 2 diabetes mellitus (T2DM) and obesity. The present narrative review explores potential interactions between the gut microbiome and GLP-1 RAs. Limited research has been conducted at the intersection of the gut microbiome and GLP-1 RA therapy. Therefore, this review focuses on potential relationships among GLP-1 RA, the microbiome, body weight, dietary changes, and gastrointestinal symptoms. The review of the current literature reveals significant gaps, particularly concerning the role of diet in mediating or confounding any impact of GLP-1 RA medications on the gut microbiome. Therefore, the body of the review is structured as a series of proposed directional and causal relationships. The limited available evidence suggests changes in behavior, diet, and weight loss resulting from GLP-1 RA treatment are the primary drivers of microbiome changes observed after GLP-1 RA treatment. The review concludes by proposing directions for future studies to clarify the complex interplay between GLP-1 RAs, the gut microbiome, diet, and obesity management.

Inborn errors of immunity (IEIs), also known as primary immunodeficiencies, are a group of genetic disorders affecting the development and function of the immune system. While IEIs traditionally present with recurrent infections, an increasing number of cases manifest with early-onset severe atopy, including atopic dermatitis, food allergies, asthma, and allergic rhinitis—features that are often overlooked. This can lead to delayed diagnosis and treatment, which is crucial for IEI patients due to the risk of severe infections. We conducted a literature search and reviewed all IEIs that can present with early-onset severe atopy. The hallmark features of these disorders often include early-onset, persistent, and severe atopic dermatitis, food allergies, and recurrent episodes of asthma, which may be refractory to treatments. Additionally, we discuss the importance of recognizing such severe atopy as a potential indicator of an underlying immune deficiency, particularly when accompanied by unusual infections, growth failure, or autoimmunity. This review aims to raise awareness of this association and emphasize the need for early diagnosis and genetic testing in patients with atypical or treatment-resistant allergic diseases, allowing for more timely diagnosis of underlying immunodeficiencies and appropriate treatments.