Metformin, a type 2 diabetes drug that has been used for over 60 years, has now been found to significantly affect the brain, according to a study by the Baylor College of Medicine in the US. The study identified a brain pathway that the drug appears to work through, including the effects it has on biological processes in other areas of the body. The findings could lead to new types of treatment. The researchers also identified the specific neurons metformin was affecting, potentially leading to more targeted treatments. The discovery could potentially help improve the safety of the drug beyond its use in the human body and potentially improve its safety.