How Excessive Antibiotic Use May Influence Anxiety Disorders
Recent findings suggest that overusing antibiotics can disrupt the gut microbiome and may be linked to higher levels of anxiety, according to a study published in Molecular Psychiatry. Researchers from the First Affiliated Hospital of Chongqing Medical University examined how these medications alter gut bacteria and whether those changes could contribute to mental health challenges, particularly increased anxiety.
The Gut Brain Communication Pathway
The digestive system hosts countless microbes that communicate with the brain through the gut brain axis. This biological connection plays a key role in maintaining emotional balance.
Researchers Highlight Potential Mental Health Risks
The research team explained, Antibiotics are widely used in medicine and may serve as a risk factor for mental health. To better understand their impact, we observed mental disorder symptoms in mice and patients who received them and explored possible mechanisms.
What the Mouse Experiments Revealed
In the first phase of the study, scientists gave antibiotics to mice, monitored their behavior, and analyzed gut microbiome samples. They compared these results to those from mice that did not receive antibiotics. Ke Xu, Yi Ren, and colleagues reported anxiety like behaviors alongside:
altered gut microbiome composition mainly Firmicutes and Bacteroidota
reduced short chain fatty acids SCFA
disrupted gut brain lipid metabolism
lower acetylcholine levels strongly associated with anxiety symptoms
Findings From Human Participants
In the second phase, the team collected stool and blood samples from 3 groups: 55 people who recently used antibiotics, 60 who had not taken them, and 60 healthy controls. They also recorded self reported anxiety levels. Individuals who had taken antibiotics showed patterns similar to those seen in mice, including elevated anxiety, altered microbiomes mainly Firmicutes, decreased SCFA, disrupted lipid metabolism, and reduced acetylcholine levels.
Overall Conclusions From the Study
Overall, antibiotic use was associated with:
anxiety like behaviors in mice
higher anxiety levels in humans
decreases in certain beneficial gut bacteria especially Bacteroides
lower acetylcholine levels in both the gut and brain
A Potential Way to Reverse Some Effects
The researchers found that some negative effects could be mitigated. They noted, Exogenous intervention with methacholine a derivative of acetylcholine effectively relieved anxiety symptoms and suppressed activation of hippocampal microglial cells in antibiotic treated mice.
Final Thoughts
The study suggests that frequent antibiotic use may alter gut microbiome balance and contribute to increased anxiety, potentially affecting overall mental health. Future research may explore therapeutic strategies aimed at restoring microbial equilibrium following antibiotic treatments.
