Monster Mayhem Causing Queasy Stomachs

"Cloverfield" is the first adrenaline-pumping monster hit of the year, bringing in more than $40 million dollars on its opening weekend. The thriller is told from the point of view of five young New Yorkers using their handheld camera. But for some viewers, being "part" of the movie is making them sick -- literally.

One blogger on the popular movie database IMDB.com said, "I had to get up and leave the theater for nearly 20 minutes just to keep from hurling." Other moviegoers have reported being nauseated and dizzy.

Most viewers are unaffected by the film, but for those who are, experts say the problem is in their heads.

"This is a classic case of vertigo," said Dr. Michael G. Stewart, chairman of otorhinolaryngology (ear, nose and throat medicine) at NewYork-Presbyterian Hospital/Weil Cornell Medical Center. "You can look around and feel like things are moving, when they aren't."