Researchers at St. Joseph’s Healthcare Hamilton and McMaster University have found that providing clinical (low) doses of penicillin to pregnant mice and their offspring results in long-term behavioral changes.
These changes include elevated levels of aggression and lower levels of anxiety, accompanied by characteristic neurochemical changes in the brain and an imbalance in their gut microbes. Giving these mice a lactobacillus strain of bacteria helped to prevent these effects.
The study was published in Nature Communications and was funded by the United States Office of Naval Research.
- Ruling Out Penicillin Allergy by Testing Inpatients Saves Money
- Many doctors still don’t know facts about penicillin allergy
- Message from CDC regarding the recent shortage of Penicillin G benzathine in the United States
- Most people mistakenly believe they’re allergic to penicillin
“In this paper, we report that low-dose penicillin taken late in pregnancy and in early life of mice offspring, changes behaviour and the balance of microbes in the gut. While these studies have been performed in mice, they point to popular increasing concerns about the long-term effects of antibiotics,” says Dr. John Bienenstock, Director of the Brain-Body Institute at St. Joseph’s Healthcare Hamilton and Distinguished Professor at McMaster University.
“Furthermore, our results suggest that a probiotic might be effective in preventing the detrimental effects of the penicillin.”
Other studies have shown that large doses of broad-spectrum antibiotics in adult animals can affect behaviour. But there haven’t been previous studies that have tested the effects of clinical doses of a commonly-used, narrow-spectrum antibiotic such as penicillin on gut bacteria and behavior.