Effectiveness of double-dose oseltamivir for pediatric patients with severe 2009 pandemic influenza A H1N1

Purpose: We aimed to evaluate the use and safety of double dose oseltamivir for patients manifesting severe respiratory symptoms or showing no improvement of clinical symptoms after 72 hours’ treatment with the usual oseltamivir dosage. Methods: We analyzed the clinical features of 2009 influenza A H1N1 inpatients who had been admitted to a university hospital’s Department of Pediatrics between August 2009 and January 2010. The Influenza A H1N1 diagnoses were confirmed by real-time reverse transcriptase polymerase chain reaction. Results: The study participants numbered 157 (mean age, 5.0 years; male-to-female ratio, 1.1:1). Among them, twenty (mean age, 5.2 years) were administered double dose oseltamivir. This double dose group showed higher peak body temperatures and more abnormal radiologic results than the other, usual-dose group. The mean time duration between high fever and afebrile status after initiation of double-dose oseltamivir administration was 2.1 days, whereas that within the usual-dose group was 1.7 days. There were no adverse effects in the patients treated with double-dose oseltamivir. Conclusion: Double-dose oseltamivir was well tolerated in patients with severe 2009 influenza A H1N1 infection.(Allergy Asthma Respir Dis 2014;2:64-69)