Drinking

This proficiency, and its companion proficiency, Eating, is important to many humanoids, including centaurs, satyrs, and wemics. A successful check indicates that the humanoid can consume up to twice as much as normal at one sitting. This will allow the humanoidto go twice as long without drink before beginning to suffer adverse effects. If alcoholic beverages are involved, a successful check allows the humanoid to consume twice as much before adverse effects begin to bother him.

[Complete Book of Humanoids]