Methylene blue.
Hackett
E R
ER
Kline
D G
DG
D002490:Central Nervous System / Q000187:drug effects*; D004396:Coloring Agents / Q000009:adverse effects*; D006801:Humans; D007203:Indigo Carmine / Q000009:adverse effects; D008751:Methylene Blue / Q000009:adverse effects*
D004396:Coloring Agents; D007203:Indigo Carmine; D008751:Methylene Blue