Most prescriptions written for psychiatric medication, including antidepressants, antianxiety drugs and antipsychotics are intended for psychiatric problems, according to a study sponsored by the Substance Abuse and Mental Health Services Administration (SAMHSA) and published in the journal CNS Drugs.

Psychiatric medications are some of the most widely prescribed of all drug classes in the United States. In fact, some policy makers and physicians have grown concerned in recent years that psychiatric drugs are being prescribed frequently for non-psychiatric conditions. The practice is called off-label prescribing: the label in this case being the specific indication for which the U.S. Food and Drug Administration (FDA) has approved a drug.

Off-label prescribing is not illegal, but it can carry the risk of exposing people to treatment that either is ineffective or has unexpected side effects. Off-label prescribing of psychiatric medication can occur both within the world of psychiatry, such as the trend toward prescribing some antipsychotic drugs for depression when they have not been approved by FDA for that condition, or outside of psychiatric condition.

To determine the degree to which psychiatric drugs were prescribed for conditions other than psychiatric problems, Tami Mark, PhD, from the media company Thompson Reuters in Philadelphia, analyzed prescribing patterns of psychiatric drug prescriptions. The data were provided by the 2005 National Disease and Therapeutic Index, which tracks the prescribing patterns of 4,000 physicians on a quarterly basis.

Mark found that psychiatric drug prescribing was largely limited to psychiatric disorders. Almost 99 percent of antipsychotic prescriptions were for a psychiatric disorder, as were 93 percent of antidepressants. Antianxiety medication was slightly different, however, with nearly a third of prescriptions intended for non-psychiatric problems.

“From this study it seems clear that psychiatric medications are for the most part being prescribed for treating people with psychiatric conditions,” said SAMHSA administrator Pamela S. Hyde, JD, about the study. “Yet, as clinicians broaden their use of psychiatric medications to a variety of mental illnesses, research and education are needed to ensure that the uses are appropriate.”