HARTFORD, Conn. (CBSNewYork/AP) — The Connecticut woman who underwent a face transplant five years ago after being attacked by a chimpanzee is back in a Boston hospital after doctors discovered her body is rejecting the transplant.

Charla Nash says doctors have decided to end an experimental drug treatment and put her back on her original medication in the hopes of reversing the rejection.

Nash had been taking part in a military-funded experiment in which doctors at Boston’s Brigham and Women’s Hospital tried to wean her off the anti-rejection drugs she had been taking since the 2011 operation.

Nash tells The Associated Press she would appreciate any prayers and is confident her participation in the experiment will provide information to help treat disfigured soldiers returning from war.

The U.S. military paid for Nash’s full face transplant, as well as face transplants for a small group of other civilians.

About 35 full or partial face transplants have been performed worldwide since the first one was done in France in 2005. The Defense Department estimates 560 soldiers have suffered severe facial wounds in Iraq and Afghanistan. Of those, about 50 or 60 might be candidates for a face transplant, said Dr. Brian Pfister, a portfolio manager for the U.S. Army Medical Research and Materiel Command’s Clinical and Rehabilitative Medicine research program.

In 2009, Nash lost her nose, lips, eyelids and hands when she was mauled by a 200-pound pet chimpanzee named Travis that belonged to her friend and employer, Sandra Herold, in Stamford. Doctors also had to remove her eyes because of a disease transmitted by the chimp.

She also underwent a double hand transplant, but it failed when her body rejected the tissue. A GoFundMe account was set up to help raise money for prosthetic hands, which would not be covered by the Department of Defense.

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