After paying $9 for diet soda and chewy pretzels nuggets with slimy nacho sauce, you'd think nothing could make you more nauseated.

But some moviegoers have found the megahit Cloverfield tough to stomach, saying that it made them headachy, dizzy or distressingly nauseated.

At the Loews theater complex in Cherry Hill, a ticket-counter sign warns that the film can create a sense of motion-sickness.

It's not the quality of the monster mash-up, it's the shaky shock-umentary camera style – with tilting and even sideways views, vertigo-inducing ups and downs, and in-focus/out-of-focus effects.

"When the jerkings lasted a while, that's when it was uncomfortable," said Ken Wunsch, 46, of Camden, who said he felt dizzy during the film.

As if that's not enough, what the camera sees and hears – supposedly shot by a normal guy as Manhattan comes under attack - is also quite gut-wrenching. Crashing, screaming, running, horror and oblivion. Wait. Calm for a moment or two. Catch your breath. Then more crashing, screaming, running, gasping, panting, smoke, "Oh my God! Oh my God!"

Hay Huang, 14, of Camden, has seen the movie twice – even though it gave her a headache, which made her a little sleepy. "I sat there, but I had to look away," she said.

Mark Defeo, 17, of Haddonfield, part of a group of teens who'd just seen the film, said he felt dizzy, especially at the beginning, when partygoers were running downstairs from a rooftop. Afterward, he gradually got used to the roaming camera, he said.

A half-dozen pals, though, said they weren't bugged a bit. Chris Colameco, 14, of Haddonfield, joked that he never gets motion-sickness, probably because "my mother went on Gravitron" – a whirling Ocean City ride – "when she was pregnant with me."

Some people are predisposed to motion-sickness, while many others aren't, explained Steven Galetta, director of neuro-ophthalmology at the University of Pennsylvania Medical Center.

"I got sick watching the trailer," he said. "I'm not going to see the movie, in fact, because I know I'll get sick from it."

In tracking objects, our eyes use five different systems, including the inner ear's vestibular system that's tied to our sense of balance, he said.

So sharp camera movements – especially coupled with bursts of light and sudden sounds – can be disturbingly disorienting.

"They're making you shift through all these systems, very rapidly, and that's what is causing visual confusion," he said.

What's more, the auditory and vestibular systems share nerve pathways, creating a kind of "excessive feed into the brain stem," resulting in nausea.

As for those who felt headachy, "they probably got motion-induced migraine," he said.

Migraines can make people feel faint – as can gore. So even as terror escalates heart rates, gruesome graphic scenes can have the opposite effect, he said.

"So you're getting a sensory barrage of emotional, auditory, vestibular and visual information, and some of it sounds like it's deliberately contradictory."

Al Blunt, 44, of Lumberton, was glad that he only got a headache. The similarly "jittery" Blair Witch Project bothered him much more. "I was sitting in the second row and I got really sick, nauseated," he said. He even had to leave the theater for a few minutes until he felt settled again. This time he sat toward the back.

Janine Blunt, 42, said she was fine. "It was annoying at first. I had to look away a little, but I got used to it," she said.

The Body Wars ride at Disney World bothered Rob Gill, 35, of Cherry Hill, but not Cloverfield. "I felt the adrenaline rush, yeah," he said, but otherwise felt fine. After all, unlike during the ride, his seat was not shifting underneath him.

"I loved the movie. I had no physical reaction to it," said Chip Swain, 36, of Mount Laurel. He actually liked the jumpy camera work, even though it reminded him of the amateur videos of the 9/11 terrorist attacks.

In Cloverfield, New York is under siege again, and building collapses abound.

"You probably couldn't do this movie five years ago, because it's too fresh," said Gill.

Janine Blunt agreed, saying the camera work made it all seem more real.

"You could imagine being there," she said.