L-carnosine has garnered some scientific interest for its potential in mitigating radiation sickness, primarily based on preclinical and animal studies. Carnosine is a naturally occurring dipeptide (β-alanyl-L-histidine) found in high concentrations in muscle and brain tissues. Its appeal in the context of radiation sickness lies in its antioxidant, metal-chelating, and anti-glycation properties, which could theoretically protect cells from oxidative damage induced by ionizing radiation.

Several animal studies (notably with mice and rats) have reported that carnosine administration before or after radiation exposure can reduce oxidative stress markers, protect against DNA and cellular damage, and improve survival rates. For example, Russian research from the late 20th century explored carnosine's radioprotective effects and found improvements in hematological parameters and decreased mortality when administered post-irradiation. Some contemporary studies have also observed reduced levels of lipid peroxidation and improved tissue repair in irradiated animals treated with carnosine.

However, despite these promising findings, there is a lack of robust human clinical trials confirming efficacy or safety in the context of radiation sickness. Regulatory authorities do not recognize carnosine as a standard therapy for this condition. Thus, while there is a scientific rationale and preliminary evidence from animal models, the overall quality and quantity of evidence are limited, justifying a low-to-moderate rating.