pissed as a newt informal
pissed out of one's head informal
pissed out of one's mind informal

'Pissed as a newt,' said the caretaker, and went back into his office.

("Pissed as a newt" is a British slang term for very drunk.)

'Pissed as a newt, drunk as a skunk,' she giggled.

"Oh, aye," Margo grumbled, "an' you'll end pissed as a newt again, like as not!"

"Rory, you're pissed as a newt.

'Pissed as a newt,' said Ricky.

Hendry, who had appeared in the television series The Avengers (1961-1969) and, according to Anderson, "was always drinking", performed the stunt sequence depicting the aftermath of the Dove crash while drunk: "... he was pissed as a newt, and it was as much as he could do to stagger away.