Methylene blue helps brain cells use oxygen more efficiently to make energy after they’ve been starved.

After brain cells are starved and then get oxygen and sugar back, methylene blue helps them make more of their main energy molecule.

When brain cells are starved of oxygen and sugar and then get them back, giving them methylene blue right after helps more of them survive.

Unlike some toxins, methylene blue doesn’t make harmful free radicals in brain cells after they’ve been starved.

Giving methylene blue while brain cells are still starved makes things worse — it only helps if you wait until oxygen and sugar are restored.

In a lab test with mouse brain cells, a chemical called methylene blue makes the energy-producing parts of the cells work harder without using energy to make ATP, while another chemical called azure I doesn’t do anything. This suggests methylene blue might be messing with how the cells normally control their energy production.