Three high school students in Madison, N.C., were sent to the hospital after they ingested a form of synthetic marijuana and were sickened, The Citizen-Times reported.

Madison High’s principal, Tony Tipton, said the students began acting strangely in class on Monday – one student fell to the floor and had convulsions, and the other two were pale and passive.

Peers reported the students had inhaled Mary Joy, a synthetic marijuana, which is touted as incense and sold in gas stations and on the Internet.

Smoking Mary Joy can lead to elevated heart rates, paranoia, vomiting and hallucinations.

The students now face disciplinary action from the school, Tipton said.

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