High Dose of Antidepressants Increases Risk for Suicidal Behaviour in Children and Young Adults

Intake of high doses of antidepressants may elevate the risk of suicidal behavior in children and young adults, a new study reveals.

Researchers at the Harvard School of Public Health, Boston, found that children and adults who are prescribed  high doses of antidepressants at the beginning of the therapy increase the risk of self harm during the first 90 days of the treatment.

A meta-analysis conducted earlier by the U.S. Food and Drug Administration of antidepressant trials suggests that children who take antidepressants had a two-fold increase in suicidal tendencies compared to their counterparts who received placebos.

In the current study, the researchers examined both suicidal behavior and antidepressant dosage and whether or not the risk of self harm depended on the age of the patient.

For the study, the researchers worked on the data of 162,625 people who were diagnosed with depression at the start of the antidepressant treatment. The treatment was with selective serotonin reuptake inhibitor in prescribed doses and at higher than approved  doses, from 1998-2000.

The researchers observed  that the rate of suicidal behavior among those taking high doses of antidepressants at the start of the therapy was twice as high in young adults compared to their counterparts who received the prescribed doses.

According to the researchers, this corresponds to an additional event of 'deliberate self harm' (DSH) for every 150 patients treated with high doses of therapy, according to Science Codex. Among adults of age 25-64 the difference in risk for suicidal behavior was null. The study did not examine why higher dose triggers higher risk of suicide in the younger population.

"Considered in light of recent meta-analyses concluding that the efficacy of antidepressant therapy for youth seems to be modest, and separate evidence that dose is generally unrelated to the therapeutic efficacy of antidepressants, our findings offer clinicians an additional incentive to avoid initiating pharmacotherapy at high-therapeutic doses and to monitor all patients starting antidepressants, especially youth, for several months and regardless of history of DSH," researchers explain.

The findings was published in JAMA Networks Journals.