OTC
adj.adj. behaving in a way that is way too much or out of control. You use this when someone is acting crazy or doing something much more intense than they should.
adj. exceeding the bounds of acceptable or reasonable behavior; excessive or out of control. Often used predicatively to describe a person's actions or emotional state in informal contexts.
He was acting totally OTC at the party last night.
The argument started over something small, but his reaction was completely OTC and made everyone uncomfortable.
While a bit of excitement is expected during the finals, the fans' behavior became OTC when they started throwing objects onto the field, forcing the referee to pause the match.
Acronym for 'over the counter' in medical contexts, but used as 'over the cliff' or 'out of control' in slang; typically follows a linking verb like 'be' or 'get'.