'Nail Files' Sued -- You EXPLOITED My Medical Emergency

A limo driver is suing the people behind the TV Guide reality show "Nail Files" -- claiming the show RECORDED him when he went into diabetic shock ... and made it appear like he was DRUNK.

According to the lawsuit, filed in L.A. County Superior Court, Fred Busby claims he was dispatched by his limo company to pick up celebrity manicurist Katie Cazorla and drive her to the airport last year.

Busby claims Cazorla was accompanied by a reality TV crew from 495 Productions -- which also produces "Jersey Shore" -- but Busby insists he NEVER consented to be on the show.

During the drive to LAX, Busby -- who says he's a diabetic -- claims he "felt his blood sugar levels dropping and he started sweating and feeling disoriented."

According to the suit, Fred claims the last thing he remembered was a passenger screaming, "Is this guy drunk?"

Fred claims when he came to ... the 495 cameraman repeatedly asked him for permission to use the footage from Fred's medical emergency, but Fred "emphatically and unambiguously said, 'No.'"

But Fred claims "Nail Files" aired the footage anyway -- violating his right to privacy and making him out to look like someone who drove while drunk.