The way the mentally handicapped kid is treated may anger some, although it's clearly not meant to be glorified. All the characters in this movie, minus the autistic kid are very unlikable and arrogant.
The scenes that portray the death of some characters are not graphic and are used in a comedic manner, but some are mildly intense, and might upset certain viewers.
A scene showing many people vomiting at the same time might disgust some viewers.
Shows a woman suffering from anorexia
A woman screams and shouts at people after her daughter dies, which may be frightening or upsetting for some viewers.