Common Acne Antibiotic May Reduce Risk of Schizophrenia in Teens

According to the results of a new study, doxycycline, an antibiotic commonly prescribed to treat acne, may lower the risk of schizophrenia in adolescents, suggesting potential for repurposing antibiotics to prevent mental illness.

A widely used antibiotic could help reduce the chances that some young people will develop schizophrenia, according to a new report, published Wednesday in American Journal of Psychiatry.

Scientists have found that teenagers receiving mental health care who are prescribed doxycycline were significantly less likely to develop schizophrenia later in life than those treated with other antibiotics.

Doxycycline, a tetracycline class antibioticis widely prescribed for bacterial infections, including respiratory and skin diseases, sexually transmitted diseases, and certain forms of acne.

Experts believe the results suggest a potential new use for a drug existing and widely available as a preventive treatment for serious mental illnesses.

Another study, published in December 2024, also concluded that doxycycline can be used in young adults.

Understanding schizophrenia and its early onset

Schizophrenia is a serious mental disorder which typically begins in early adulthood and is often characterized by hallucinations, delusions and disorganized thinking.

Finding ways to reduce the risk of developing this condition has long been a great challenge for researchers of mental health.

To explore possible prevention strategies, a team of scientists from the University of Edinburgh, in collaboration with colleagues from the University of Oulu and University College Dublin, analyzed healthcare data of Finland using advanced statistical models.

The study examined health records of more than 56,000 teenagers who had received antibiotics while attending mental health services.

Patients treated with doxycycline had a 30 to 35% lower risk of later developing schizophrenia compared to those who received other types of antibiotics.

The research team believes that this andprotective feat may be related to the impact of doxycycline on inflammation and brain development.

How doxycycline can protect the brain

Previous studies have found that doxycycline can reduce inflammation in brain cells and affect the synaptic pruninga normal developmental process in which the brain eliminates and strengthens neuronal connections. Excessive pruning has been linked to the onset of schizophrenia.

Further analysis confirmed that the reduced risk was not simply due to the participants being treated for acne rather than infections, and was unlikely to result from other differences not detected between groups.

“About half of the people with schizophrenia whose data we analyzed had previously attended mental health services for children and adolescents due to other mental health problems“explains Ian Kelleherprofessor of Child and Adolescent Psychiatry at the University of Edinburgh and lead author of the study, cited by .

“At present, however, we do not have any interventions that are known to reduce the risk of developing schizophrenia in these young people. This makes these exciting discoveries“, he adds.

“Given that the study was observational in nature and not a randomized, controlled clinical trial, means that we cannot draw definitive conclusions about causality“, notes Kelleher.

“But this is an important signal to further investigate the protective effect of doxycycline and other anti-inflammatory treatments in adolescent psychiatry patients as a way of potentially reduce the risk of developing serious mental illness in adulthood”, he concludes.