Tyrese Rushed to ER: I was POISONED!!

Tyrese says tainted seafood did a major number on his insides -- sending him to an L.A. hospital last night ... TMZ has learned.

According to a rep, Tyrese is recovering at home today ... but before he left the hospital he fired off a twitpic of his feet in the hospital bed -- and the message, "ER...pray for me."

Ty's rep says the singer/actor started feeling sick almost immediately after he went out for a meal yesterday.