Summary Description: Methylene blue is a synthetic phenothiazine derivative with a broad spectrum of uses in research and medicine, including as a redox-active dye, antidote, and pharmacological agent. In addition to its classic roles in the treatment of methemoglobinemia, distributive shock, and as a surgical dye, recent research has demonstrated potent anti-aging and neuroprotective properties. Methylene blue improves mitochondrial function, reduces oxidative stress, and delays cellular senescence by acting as an alternative electron carrier in the mitochondrial respiratory chain. It has shown efficacy in enhancing cognition, supporting wound healing, delaying skin aging, and protecting neural tissue from degeneration and injury. This versatile compound is now actively investigated for its potential to combat age-related diseases, neurodegeneration, and to support human longevity1-4.