Antidepressants may not be equally effective at treating various symptoms in depression, according to a new study published online in JAMA Psychiatry.

In their research, the authors analyzed data from 9 clinical trials, which totaled over 7,000 patients with major depression, the most common form of the disorder.

Read: How Antidepressants Work In The Brain: A Comprehensive Guide​

Patient-reported data from one of the trials was used to identify clusters of symptoms from a checklist. This method was used instead of the typical one that measures overall depression based on a questionnaire that asks about a variety of symptoms.

From this trial, the authors identified three specific clusters of symptoms and replicated them in a second trial.

“These clusters differ in their responsiveness to treatment both within and across different antidepressant medications,” the authors conclude in their paper.

They also found antidepressants in general were more effective for core emotional symptoms, like a loss of interest in activities, rather than for sleep or atypical symptoms.

Several of the study authors disclosed financial ties to the pharmaceutical industry, MedicalXpress noted.

About one in 10 Americans aged 12 and over take antidepressant medication, according to the Centers for Disease Control and Prevention.

There are many different antidepressants available, and they work in different ways. To learn more about the various types of medication, how they work, and their side effects, check out Medical Daily’s comprehensive guide, ‘How Antidepressants Work In The Brain.’

See also: Antidepressant Side Effects: Do SSRIs Block Sexual Pleasure And Orgasm?

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