The action of passing in and out of consciousness when someone takes enough, or too much depressant class drugs. Often a state purposefully attempted by the downer class user for the euphoria it envokes. Resembles passing out from not enough sleep. Can be dangerous if one passes out and stops breathing, or chokes on their vomit while unconscious.
Brian: Jimmy was so high this morning after his breakfast shot of heroin, he ended up nodding out into his breakfast meal of pancakes, and got syrup all over his face.