The Pentagon is investigating an anti-malaria drug that is known to have psychiatric side effects; the review was reportedly ordered a week after the massacre that left 17 Afghans dead, allegedly at the hands of a U.S. serviceman.
The Daily Mail reports it is unknown if alleged gunman Staff Sgt. Robert Bales was given the drug Mefloquine.
The report said the military has known about problems with Mefloquine for some time and nearly banned it in 2009. Instead, its use was restricted, specifically not given to soldiers who had suffered brain injuries.
It is known that Bales suffered a brain injury during his last tour of duty in Iraq.
The Pentagon said the review is not related to the massacre.
"The department wide review of Mefloquine prescription practices has no connection to the Staff Sgt. Robert Bales investigation," Defense Department spokeswoman Cynthia Smith said in a statement. "Assistant Secretary of Health Affairs Jonathan Woodson requested this review in January to ensure each service conducts proper screening, patient education, and medical documentation."
Smith would not comment on reports the review came after the killings.
Mefloquine has been linked to numerous suicides and killings in the military over the years. It can cause paranoia, hallucinations and psychotic behavior.
"Mefloquine is a zombie drug. It's dangerous, and it should have been killed off years ago," said Army Major and epidemiologist Dr. Remington Nevin.