New research challenges long-standing concerns about the antiviral drug oseltamivir, known as Tamiflu, and its potential link to serious neuropsychiatric events in children. Instead, the study attributes such symptoms to the influenza virus itself and shows that Tamiflu treatment halves the risk of these complications. The findings, based on a large analysis of pediatric health records, aim to reassure families and doctors about the drug's safety.
For years, reports of seizures, confusion, and hallucinations in children taking oseltamivir for flu treatment raised doubts about the drug's safety. A new study from Monroe Carell Jr. Children's Hospital at Vanderbilt, published in JAMA Neurology, overturns this view by demonstrating that influenza is the primary cause of these neuropsychiatric events.
The research analyzed de-identified health records of 692,295 children and adolescents aged 5-17 enrolled in Tennessee Medicaid from July 1, 2016, to June 30, 2020. Over this period, 1,230 serious events were recorded, including 898 neurologic incidents like seizures, encephalitis, altered mental status, ataxia, vision changes, dizziness, headaches, and sleep disorders, plus 332 psychiatric cases such as suicidal behaviors, mood disorders, and psychosis or hallucinations.
Principal investigator James Antoon, MD, PhD, MPH, an assistant professor of Pediatrics, explained the key insights: "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."
Three main discoveries supported this conclusion. First, children with influenza experienced higher rates of neuropsychiatric events than those without flu, irrespective of treatment. Second, among flu patients, oseltamivir users had about a 50% lower incidence of such events compared to untreated peers. Third, children without flu who received oseltamivir preventively showed event rates similar to those with no flu exposure.
"Taken together, these three findings do not support the theory that oseltamivir increases the risk of neuropsychiatric events," Antoon added. "It's the influenza."
Senior author Carlos Grijalva, MD, MPH, a professor at Vanderbilt University Medical Center, stressed the importance of timely intervention: "These flu treatments are safe and effective, especially when used early in the course of clinical disease."
Antoon highlighted the relevance amid recent seasons: "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. 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."
The study, funded by the National Institutes of Health, seeks to build confidence in oseltamivir's role in mitigating flu complications.