Polymyxins are a group of antibiotics derived from the soil bacterium Bacillus polymyxa, discovered in the 1940s. Originally identified in 1947, these peptides exhibit significant antibacterial activity against a range of Gram-negative bacteria. The discovery of polymyxins marked a pivotal advancement in antibiotic therapy, particularly during an era when multidrug-resistant infections began to emerge. Polymyxin B and colistin (polymyxin E) are the most commonly used members of this class, primarily targeting infections caused by resistant strains of bacteria such as Pseudomonas aeruginosa and Acinetobacter baumannii. Despite their effectiveness, the use of polymyxins has declined due to their nephrotoxicity and neurotoxicity; however, rising resistance to other antibiotics has led to a resurgence in their clinical application. Today, polymyxins serve as a last-resort treatment option for serious infections, emphasizing their continued relevance in addressing the challenges of antibiotic resistance in modern medicine.

Elevated levels of Polymyxins can indicate increased exposure to antibiotic agents, often reflecting an ongoing response to bacterial infections or imbalances within the microbiome. High Polymyxin levels may suggest a higher risk of resistance development in certain bacteria or an adverse effect on beneficial microbial populations. Conversely, low levels of Polymyxins could signify a balanced gut environment with effective microbial diversity, but it may also indicate an inadequate response to infection or a lack of necessary antimicrobial agents. Understanding these levels is crucial for assessing gut health and the impact of antimicrobial treatment strategies.

Polymyxins are critical components featured in the Gut Zoomer panel, which assesses the presence of specific antibiotics produced by certain gut bacteria. These markers play a vital role in understanding gut microbial communities and their influence on overall health. By identifying polymyxins levels, practitioners can gain insights into potential dysbiosis and antibiotic resistance, helping to inform targeted therapeutic strategies for optimizing gut health and restoring microbial balance.