Methylene blue fixes a key enzyme that helps brain cells start using sugar for energy 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.

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.

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

Methylene blue helps brain cells take in more sugar, which they need to make energy.

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