A Common Antidepressant Might Help Bacteria Become Superbugs

A common antidepressant, suggested under the brand name Prozac, suggests a new study from Australia. The study, published in International Environment, found that fluoxetine was capable of inducing antibiotic resistance in laboratory strains of Escherichia coli.

Fluoxetine is a selective serotonin reuptake inhibitor (SSRI), a class of drug that prevents certain neurons in the brain from reabsorbing serotonin, a neurotransmitter. People with clinical depression often have less serotonin available, and SSRIs boost these levels, helping treat the condition to some extent.

In recent years, though, there is some evidence that SSRIs such as fluoxetine can also kill off bacteria and other microbes, thus being used as antimicrobial agents. But the flip side to this realization is that the fluoxetine can prevent antibiotic resistance in the environment, since some of the drugs ends up in our bodies after it flushes through our bodies.

The current study is all about the first to test out that theory.

The researchers exposed an antibiotic-susceptible strain of E. coli to different concentrations of fluoxetine. Then they're coming together and they're cooking with a mix of antibiotics. The bacteria that were lived through the fluoxetine bath were quick to develop mutations against the widely used chloramphenicol antibiotics, amoxicillin, and tetracycline, they found. This resistance was also seen against other antibiotics in the same drug class. And much like a typical antibiotic, the largest dose of fluoxetine has been obtained, the quicker surviving bacteria.

Bacteria can learn to defeat antibiotics in lots of different ways. And a major reason why antibiotic resistance is so much that they can not avoid a whole class of antibiotics at the same time. Fluoxetine might affect antibiotics, but it seems to be more likely to kill antibiotics in the study, making cross-resistance more likely. When Guo and his team studied the genetics of E. coli exposed to fluoxetine, they found mutations already known to help These mutations allow the bacteria to essentially be a drug before it kills them.

"This finding provides strong evidence that fluoxetine directly causes multi-antibiotic resistance via genetic mutation," senior author Jianhua Guo, a researcher at the University of Queensland's Advanced Water Management Center, said in a statement.

It's just not fluoxetine, either. Other antibiotics, such as antimicrobial triclosan, can be used to create antibiotic resistance. Triclosan, et al, et en un peu et de la santé et de la santé et de la santé et de la santé.

At this point, the authors admit, we have no idea just how far-reaching the presence of fluoxetine in the environment could be, nor its full impact on antibiotic resistance. Strains of strains of other strains of strains E. coli or other bacteria found in the gut. But despite these unanswered questions, and given how widespread fluoxetine is used, there is a lot to be worried about.

Said lead author Jin Min, also of the University of Queensland: "It has already been an invisible factor in the spread of antibiotic resistance, but we should consider this a warning."