An exhausted JUSTIN BIEBER recently suffered a terrifying collapse, The ENQUIRER reports exclusively.

The teen idol has lost 10 pounds, and a grueling work schedule is taking a devastating toll on his health, according to a pal.

"Justin is being pulled in every direction possible, and he seems to be on the brink of a complete nervous breakdown," a source close to the 16-year-old pop star told The ENQUIRER.

"The stress is phenomenal… and at one point the poor kid collapsed with exhaustion.

"If he’s not careful, success is going to destroy him."

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