"Breaking Dawn" is causing some moviegoers to tremble -- and not in delight at the sight of a shirtless Robert Pattinson.

The penultimate installment of the "Twilight Saga" series of vampire movies -- which opened Nov. 18 -- has reportedly caused seizures in at least two audience members.

Hardly the numbers of fainting viewers of last year's "127 Hours," but still...

Roseville, California, resident Brandon Gephart claims that the film's birthing scene -- which in addition to graphic gore contains blasts of blinding light -- triggered an incident when he attended the movie, causing him to convulse.

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Gephart's girlfriend, Kelly Bauman, tells Sacramento station CBS 13 [5] that Gephart suddenly began convulsing during the scene. Gephart claims that he blanked out, and only remembers waking up on the theater floor, but according to Bauman, he was "convulsing, snorting, trying to breathe.”

Gephart, who was transported by paramedics to the emergency room, is seeking help from a specialist.

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Meanwhile, a Utah woman told Salt Lake City's ABC 4 News [7] that her husband experienced similar symptoms while viewing the movie last week.

When the birthing scene came on the screen, "[My husband] started mumbling and he was blinking on and off with his eyes at that point. I was kneeling in front of him slapping his face."

The man, who wished to remain anonymous, said he has no memory of the incident.

"I didn't really remember what happened after that I think I blacked out. According to her, I was shaking and mumbling different noises," he said.

Moreover, when they returned the next day to retrieve the man's cell phone, they were told that another audience member had experienced the same thing.

Though rare, seizures of this type are not unheard of. A 1997 episode of "Pokemon" was pulled from rotation after its first airing, when 685 viewers were taken to the hospital after reportedly suffering seizures while watching the episode, in a phenomenon that the Japanese press dubbed "Pokemon Shock."

More recently, the 2010 film "127 Hours" -- which starred James Franco as hiker Aron Ralston, who was forced to cut off his own arm when he was trapped by a boulder -- racked up three faintings and a seizure during its first showing at the Toronto International Film Festival.