Green’s Dictionary of Slang

(US campus) acting in an extreme way, whether because drunk, intoxicated by a drug or just crazy.

1981		Eble Campus Sl. Mar. 5: OOC – [...] drunk, stoned, or just plain crazy.
1996		Eble Sl. and Sociability 37: Two kinds of shortening reduce words to letters. The dominant type in college slang is initialism, which names the individual letters: [...] OOC (out of control) ‘drunk, high on drugs, or acting crazy’.
1997–2002		Hope College ‘Dict. of New Terms’ 🌐 OOC adj. Abbreviation for ‘out of control,’ used to describe an extreme, surprising, or bothersome situation. May have a negative connotation.
2003		Eble Campus Sl. Nov.