The Quail Springs and Crossroads mall movie theaters posted warnings that the J.J. Abrams-directed movie, which was shot to mimic a home video recording during a monster invasion in New York, may cause some viewers to feel sick to their stomachs, KOCO-TV, Oklahoma City, reported Wednesday.

"Due to the filming method used for 'Cloverfield,' guests viewing this film may experience side effects associated with motion sickness, similar to riding a rollercoaster," the notices read.

Some moviegoers have demanded refunds or other compensation from theater managers after experiencing sickness during the film.

"I heard a few people kind of whining about it," said moviegoer Thomas Dozier. "They were talking about, like, 'I have got to get out of here.' Everyone around me was freaking out."

However, despite the apparent health risks, "Cloverfield" broke a January box office record for its opening weekend, bringing in $41 million.