You can find some very spot-on reviews of Beasts of the Southern Wild by Googling the title of the movie (in quotes) and "nausea":
reelviews.net: "To this day, I have never understood why some directors see value in filming their entire movie using a shaking, hand-held camera. The intent is to create a more gritty image and to enhance intimacy. More likely, however, it is apt to promote nausea and become a distancing factor."
All in One Boat: "I can’t give it a review here because within 30 minutes I had to leave. Not because of child cruelty but because of intense vertigo induced by shaky camera work and intensely loud music."
fromtheeditr: "When cameras are on a bumpy ride, out of focus, intentionally nausea-inducing, it is difficult to concentrate on any message the filmmaker might have for me. "
For me, it was like trying to read in a car for 90 minutes.