Irony poisoning is when one's worldview/weltshauung/reality tunnel is so dominated by irony and detachment-based-comedy, that the joke becomes real and you start to do things that are immoral or wrong from a place of deep nihilistic cynicism.
"Why would John do this to me?"
"It's irony poisoning, ma'am. Seen it a million times."
12 step recovery jargon referring to someone new who talks about how great life is, now that they'resober. Usually meaning that the person is out of touch with reality.
The new guy seems pretty happy for a dude who has no job, no money and no family. He must be on a pink cloud.