A New Study Suggests That An Ingredient Found In Antidepressants May Lead To Cases Of Antibiotic Resistance

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A new study that was conducted by scientists at the University of Queensland in Australia has suggested that a common ingredient found in antidepressants could be helping to create a resistance to antibiotics.

According to a press release by the University of Queensland, lead author Dr. Jianhua Guo studied the effects of fluoxetine, which is given to patients to help treat obsessive-compulsive disorder, depression, and eating disorders. Dr. Guo noted that while traditionally science has focused upon the overuse of antibiotics as part of the reason for the emergence of today’s superbugs, many scientists are completely unaware that the use of other medications may also be contributing to antibiotic resistance today.

Dr. Guo noted previous research that was conducted had shown that triclosan, which can even be found in toothpaste, was shown to create antibiotic resistance. Because of this, he decided to spearhead another study to determine what other common medicines may also lead to antibiotic resistance. Fluoxetine, as it turns out, is one of them.

“Our previous study reported that triclosan a common ingredient in toothpaste and hand wash can directly induce antibiotic resistance. We also wondered whether other non-antibiotic pharmaceuticals such as fluoxetine can directly induce antibiotic resistance.”

Unfortunately, when people take antidepressants, it was determined that 11 percent of the fluoxetine in the medication remains in the patient’s urine completely unchanged and heads straight to sewers everywhere, making it prevalent everywhere today.

“Fluoxetine is a very persistent and well-documented drug in the wider environment, where strong environmental levels can induce multi-drug resistance. This discovery provides strong evidence that fluoxetine directly causes multi-antibiotic resistance via genetic mutation,” according to Dr. Guo.

Dr. Min Jin, who was also involved with the new study, explained that when higher amounts of antidepressants containing fluoxetine were taken, this, in turn, greatly increased the genetic mutation which creates antibiotic resistance. However, Dr. Jin stated that further research will need to be conducted to determine how microbiota deals with this drug.

“It has previously been an invisible factor in the spread of antibiotic resistance, but we should consider this a warning. Further work is required to investigate effects of fluoxetine on antibiotic resistome in human gut microbiota.”

Antimicrobial resistance is currently a major problem, and around 700,000 people die every year as a direct result of antimicrobial-resistant infections, with that number expected to jump to a staggering 10 million people each year by 2050 unless something is done to combat the problem.

The new study, which links an ingredient in antidepressants to antibiotic resistance, has been published in Environment International.