Antibiotics are essential agents in the treatment of bacterial infections; however, their widespread utilization, including in non-therapeutic scenarios, raises significant concerns regarding unintended consequences on host physiology [1]. Intermittent or recurrent exposure to antibiotics, frequently observed in prophylactic treatment regimens, agricultural practices, and poultry farming, as well as through inappropriate clinical prescriptions and the over-the-counter availability of these medications, often disrupts microbial homeostasis within the host [[2], [3], [4]]. The colon is home to trillions of microorganisms—collectively referred to as the gut microbiota that play critical roles in nutrient metabolism, immune system modulation, and protection against pathogens [5]. The microbial dysbiosis in the gut can induce excessive production of reactive oxygen species, leading to inflammation and epigenetic stress [6]. Numerous epidemiological studies have indicated that increasing and uncontrolled exposure to antibiotics is associated with an elevated risk of gut dysbiosis linked to inflammatory diseases, including autoimmune disorders, inflammatory bowel disease, celiac disease, food allergies, asthma, and obesity, potentially through mechanisms involving inflammation and genotoxic stress [[7], [8], [9]]. Several studies have pointed out a strong association of antibiotic exposure with an increased risk of IBD and associated CRC among people of all age groups [10]. The global challenge of antibiotic resistance, coupled with alarmingly high rates of annual antibiotic consumption, underscores the urgent need for a more nuanced understanding of the role of antibiotics in the risk of developing IBD and associated CRC [11]. Broad-spectrum antibiotics (e.g., fluoroquinolones, beta-lactams) are particularly disruptive due to their indiscriminate elimination of susceptible bacterial populations within the host, which allows for the proliferation of opportunistic or resistant species, thereby compromising mucosal immunity and heightening susceptibility to inflammatory conditions [12]. The extensive range of inflammatory disorders associated with antibiotic usage, along with correlations to various classes of antibiotics, indicates that the risk is not merely a consequence of side effects; instead, it reflects a shared underlying effect across multiple antibiotics that influences systemic inflammatory responses. In light of this premise, several studies have sought to establish a link between antibiotic-induced alterations in gut health, heightened inflammatory responses, and genomic instability [13]. Nonetheless, despite these observations, the mechanistic pathways connecting antibiotic-induced dysbiosis of gut microbiota to an increased risk of inflammatory reactions in the colon remain inadequately understood.

Amoxicillin, belonging to the beta-lactam class of broad-spectrum antibiotics, is commonly consumed by people all over the world. Classified as an "Access" first-line agent by the WHO AWaRe framework, this β-lactam antibiotic is among the most widely prescribed medications in the world, including India, for both human and veterinary use. Its popularity is largely attributed to its affordability, broad-spectrum efficacy, and widespread availability in both public and private healthcare settings [[14], [15]]. Amoxicillin targets bacteria by. disrupting cell wall formation, resulting in cell lysis. This mechanism of action, however, can adversely affect beneficial bacteria in the body by killing them indiscriminately [16]. Numerous studies have indicated that amoxicillin may induce toxicological changes in various organs through mechanisms such as hypersensitivity and oxidative stress [17]. Meta-analyses and case-control studies have highlighted the potential negative impacts of amoxicillin, particularly concerning gut microbiota dysbiosis, which can contribute to cellular stress in the host and may result in chronic inflammation in the gut, including the colon [18,19]. However, there is a lack of mechanistic evidence regarding the effects of long-term amoxicillin exposure in an in vivo setting to substantiate these epidemiological findings. The current study aims to assess the impact of recurrent exposure to amoxicillin on the colon health of experimental animals. Specifically, it investigates the cumulative effects of amoxicillin after recurrent exposure, intervened by a recovery period in mice, to evaluate any potential harmful consequences associated with prolonged recurrent exposure to this antibiotic.