Sanity Potion
Sanity Potion is an unused item from Amnesia: The Dark Descent.

This potion restore some of Daniel's sanity similar to how Laudanum restores health. It can be seen in some early gameplay footage. One Sanity Potion restores one level of sanity:

  • Crystal clear (Green)
  • A slight headache (Yellow)
  • Head is pounding and hands are shaking (Orange)
  • ... (Red)

The item was never removed from the code and can still be implemented in custom maps and be used in the same way it was intended to. It is possible that the developers didn't think that the item fit in with the games lore and era, since drugs that helped with insanity were very primitive back in the 1830's. It is also possible that the developers simply found that the sanity potion made the game too easy.