FORT MADISON, Iowa (AP) – Eighteen inmates were disciplined on suspicion of using or possessing synthetic drugs at the Iowa State Penitentiary during a dangerous outbreak that has been contained.

Disciplinary records show inmates who smoked powerful synthetic marijuana acted violently, vomited, screamed and hurt themselves falling. One suffered a seizure, one had to be sprayed with chemicals and several had to be transported in wheelchairs for treatment. Inmates used everything from batteries to razor parts as heat sources to smoke the drugs, which were concealed inside foil and latex glove fingers. One inmate made a pipe from a playing card.

The incidents happened between March 22 and May 5. Department of Corrections spokeswoman Lettie Prell says the prison, which tightened its security for mail and visitors, doesn’t expect any more cases. Inmates were punished with detention and loss of earned time.