Painkiller Side Effects Blunt Effectiveness of Antidepressants: Study

The findings of a new study suggest that commonly used painkillers may interfere with the effectiveness of certain antidepressants. 

Individuals taking non-steroidal anti-inflammatory drugs (NSAIDs), such as Tylenol, Motrin and Advil, have been found to respond considerably less to a class of antidepressants known as selective serotonin reuptake inhibitors (SSRIs), which include drugs like Paxil, Zoloft and Prozac, according to research published this week by the medical journal Proceedings of the National Academy of Sciences.

U.S. researchers looked at the interactions between the commonly used painkillers and the newer generation antidepressants by conducting tests on mice and comparing the results to previous large-scale studies conducted on humans. The findings indicate that NSAIDs prevent SSRIs from boosting levels of a group of biochemicals secreted by the brain, known as cytokines, which could prevent the antidepressants from being effective, according the researchers.

In prior studies on humans, 54 percent of subjects given SSRI antidepressants said they responded favorably to them. However, when the researchers looked at only those who were taking NSAIDs at the time, that number dropped to 40% effectiveness.

The researchers say that the ramifications go beyond people being treated for depression, as SSRIs are often prescribed to patients suffering from Alzheimer’s disease, and those, usually elderly patients, are frequently on NSAIDs as well.

According to the researchers, additional clinical trials need to be conducted to determine dosages. Researchers recommended that people taking NSAIDs who also need to be placed on an antidepressant may want to consider using a non-SSRI.

SSRIs are a relatively new class of antidepressants, which help reduce symptoms of depression by preventing certain nerve cells in the brain from re-absorbing the chemical serotonin. These drugs are commonly used by millions of Americans with depression.

Although the drugs have been found to cause fewer side effects than older anti-depressants, research has shown that users of the drugs could also face an increased risk of suicides, and use during pregnancy has been linked to a risk of birth defects from antidepressants.