New research suggests that the commonly-prescribed antiviral drug, oseltamivir, marketed as ‘Tamiflu’, does not cause serious neuropsychiatric symptoms, and that these symptoms are instead caused by the influenza infection itself. The corresponding study was published in JAMA Neurology.
"Our findings demonstrated what many pediatricians have long suspected, that the flu, not the flu treatment, is associated with neuropsychiatric events. In fact, oseltamivir treatment seems to prevent neuropsychiatric events rather than cause them,” said principal investigator James Antoon, MD, assistant professor of Pediatrics at Vanderbilt University Medical Center, in a press release.
For the study, researchers analyzed health records of close to 700,000 children with an average age of 11 years old from between 2016 and 2020. Over this period, 1,230 serious neuropsychiatric events were recorded. Neurologic outcomes included seizures, encephalitis, altered mental status, ataxia/ movement disorders, vision changes, headache, and sleeping disorders, while psychiatric outcomes included suicidal or self-harm behaviors, mood disorders, and psychosis/ hallucination.
Ultimately, the researchers found that the risk of serious neuropsychiatric events increased during periods of influenza infection and that treatment with oseltamivir was linked to a roughly 50% reduction in incidence compared to periods without the drug. This, wrote the researchers, suggests that flu infection increases the risk of serious neuropsychiatric events and that oseltamivir may protect against flu-related complications.
As the research was conducted using Tennessee’s Medicaid population, the findings may not be generalizable to other populations, wrote the researchers in their study.
"The 2024-2025 influenza season highlighted the severity of influenza-associated neurologic complications, with many centers reporting increased frequency and severity of neurologic events during the most recent season," said Antoon.
"It is important for patients and families to know the true risk-benefit profile of flu treatments, such as oseltamivir, that are recommended by the American Academy of Pediatrics. These flu treatments are safe and effective, especially when used early in the course of clinical disease,” he added.
Sources: Science Daily, JAMA Neurology
