The Pentagon is set to make a move to limit the off-label use of anti-psychotic medication for the treatment of post-traumatic stress disorder, as this has been associated with accidental drug overdoses among troops.

In a letter to the services in February, Dr. Jonathan Woodson, Assistant Secretary of Defense for Health Affairs, asked for the monitoring of prescriptions of atypical antipsychotics by military treatment facilities. These drugs include risperidone and quetiapine, marketed under the brand name Seroquel.

These drugs are prescribed to treat such severe mental illnesses as schizophrenia and bipolar disorder; they are also sometimes prescribed to troops in lower doses, in order to address symptoms associated with PTSD and anxiety, such as nightmares and irritability. The drugs, however, may prove to be dangerous, even fatal, when mixed with other prescriptions.

The drugs may cause side effects that include slow heart rates and high blood sugar levels; when taken with other medications that lower respiration and heart rate, such as opiates and alcohol, they can make the problem worse.

Woodson cited in his letter that the number of prescriptions for these medications increased tenfold, from 0.1 percent to 1 percent, from 2002 to 2009. According to the FDA, 34 drug overdoses were linked to quetiapine over a one-year period, although none of these cases were fatal. Half of the cases involved other drugs.

Military death records for 2011 obtained by the Military Times, on the other hand, indicated at least 68 accidental drug tests among troops in 2009. In addition, at least 430 troops died due to drug and alcohol use in the past decade.