A fraternity at the University of Tennessee is being investigated after some members allegedly gave each other alcohol enemas over the weekend.

The university suspended its Phi Kappa Alpha chapter on Monday for 30 days or until the university makes a decision about the frat's future, the Tennessean newspaper reported.

On Saturday, a 20-year-old student was dropped off at the university's medical centre at around 1:30 a.m. with a blood alcohol level greater than 0.4, the Tennessean reported. He was in critical condition and non-responsive. He has since been released from hospital.

Police went to the frat house and found others, including three men, passed out.

After conducting interviews, police determined that the frat members had used rubber tubing to give each other alcohol enemas, a practice police said hastens alcohol's entry into the bloodstream.

"University officials are currently conducting an investigation into allegations involving the Pi Kappa Alpha fraternity chapter and incidents that occurred over the weekend," the Knoxville-based university said in a statement. "Due to the gravity of the allegations, interim sanctions have already been imposed upon the chapter and will remain in effect until the investigation is concluded and final reports are available."