When it comes to prescribing antidepressant dosages for children and young adults, more appears to be too much. A new study published in the April 28 online JAMA Internal Medicine reports that younger patients who begin taking antidepressants at higher-than-recommended doses are more likely to commit acts of deliberate self-harm (DSH), including attempting suicide.
As part of a first study to look at suicide risk by drug dosage, researchers led by Matthew Miller, MD, associate director of the Harvard School of Public Health’s Injury Control Research Center in Boston, analyzed information from a large prescription claims database. The data covered 162,625 patients between the ages of 10 and 64 years with a diagnosis of depression who started taking the medication between 1998 and 2010.
The researchers focused their analysis on three of the most commonly prescribed antidepressants – Celexa, Zoloft and Prozac. Study investigators then reviewed participant’s medical records to determine how many had committed acts of deliberate self-harm within a year of having started their medication.
Study results showed that nearly 18 percent of those in the study were started on doses higher than the recommended amount. The researchers found that patients 24 and younger who took higher doses of antidepressants were more than twice as likely to commit acts of self-harm than those who took the same drugs at lower doses. In addition, findings indicated that the risk of suicide was greatest during the first 90 days the patient was on the medication.
However, the study revealed no significant increase in the risk of self-harm among patients over 25 who were taking higher doses of the drug. Nor was there any indication of self-harm among children and teens who were taking the recommended dose.
In a commentary accompanying the published article, David A. Brent, MD, endowed chair in suicide studies and a professor of psychiatry at the University of Pittsburgh, noted that the study did not address whether dose escalation over time raised the risk of self-harm. He did, however, state that the research results lend support to guidelines that call for starting antidepressants at low doses.
Brent also acknowledged that choices for treating depression are complex. “There is no one right thing to do. It’s the obligation of the physician to explain the risks and benefits [of the drugs] and for the family to make the decision,” he told USA TODAY.