Wine of courage
From A Wiki of Ice and Fire
The wine of courage is a wine-like mixture of nightshade, bloodfly larva, black lotus root, and many secret things. It is a numbing agent which makes the drinker feel less and less with every consumption. It is created by the Astapori and given to the Unsullied at every meal from the day they are cut, so the eunuch soldiers are more able to endure pain.
- ↑ A Storm of Swords, Chapter 23, Daenerys II.