Unusual neuropsychiatric events related to oseltamivir are very rare but some cases have been reported, mainly in the United States and Japan. Here we present a rare case of auditory hallucination and suicide attempt after intake of this medication for H1N1 treatment.
Hallucinations ; Japan ; Oseltamivir ; Suicide ; United States

Oseltamivir is a substrate of P-glycoprotein, an efflux drug transporter encoded by ABCB1. The objective of this study was to assess the role of ABCB1 (c.1236C>T, c.2677G>T/A, and c.3435C>T) polymorphisms in the pharmacokinetics of oseltamivir and its active metabolite, oseltamivir carboxylate in humans. Nineteen healthy male subjects were enrolled, and their ABCB1 polymorphisms were evaluated. After the oral administration of 75 mg oseltamivir, the plasma concentrations of oseltamivir and oseltamivir carboxylate were measured. Pharmacokinetic analysis was carried out. Systemic exposure to oseltamivir and oseltamivir carboxylate was higher in the mutant group than in the wild-type and heterozygous groups. We suggest that ABCB1 polymorphisms affect the pharmacokinetics of oseltamivir in humans. Further studies in a large population are necessary to validate the results of this preliminary study (Clinical Trial Registration Information [CRIS] registry: http://cris.nih.go.kr, No. KCT0001903).
Administration, Oral ; Humans* ; Male ; Oseltamivir* ; P-Glycoprotein ; Pharmacokinetics* ; Plasma

PURPOSE: Although oseltamivir is widely used for treatment of influenza, few clinical studies of its efficacy and resistance have been performed in Korea. We evaluated the safety, side effects, and efficacy of oseltamivir treatment in Korean pediatric patients. METHODS: We analyzed 321 children diagnosed with influenza at Busan St. Mary's Medical Center, Korea, between January 2008 and June 2008 (first study period) and November 2008 and January 2009 (second study period). Patients were divided into two groups: those receiving oseltamivir treatment for 5 days and those receiving only symptomatic treatment. We investigated clinical symptoms, side effects, and resistance to oseltamivir. We also identified influenza strains and evaluated resistance to oseltamivir using an influenza virus culture. RESULTS: One hundred eighty-six patients were assigned to the treatment group, and 135 were assigned to the control group. The treatment group showed shorter admission duration (4.4 days) compared with controls (5.0 days) (P=0.000) and had fewer lower respiratory tract complications compared with controls (P<0.05). No significant statistical difference in the virus antigenic type was observed between the groups. In the first study period, virus culture showed influenza B (41.7% vs. 49.6%), A/H3N2 (7.9% vs. 8.4%), and A/H1N1 (9.4% vs. 6.5%). In the second study period, only A/H1N1 (55.3% vs. 50.0%) was isolated, except for one case of A (H3N2) in the treatment group. No differences in short- and long-term side effects, including neuropsychologic side effects, were noted between groups. There was no resistance to oseltamivir before or after treatment in the first study period. CONCLUSION: Based on our results, we suggest that osetalmivir therapy in pediatric patients is effective.
Child ; Humans ; Influenza, Human ; Korea ; Orthomyxoviridae ; Oseltamivir ; Respiratory System ; Viruses

The interaction between viral HA (hemagglutinin) and oligosaccharide of the host plays an important role in the infection and transmission of avian and human flu viruses. Until now, this interaction has been classified by sialyl(alpha2-3) or sialyl(alpha2-6) linkage specificity of oligosaccharide moieties for avian or human virus, respectively. In the case of H5N1 and newly mutated flu viruses, classification based on the linkage type does not correlate with human infection and human-to-human transmission of these viruses. It is newly suggested that flu infection and transmission to humans require high affinity binding to the extended conformation with long length sialyl(alpha2-6)galactose containing oligosaccharides. On the other hand, the avian flu virus requires folded conformation with sialyl(alpha2-3) or short length sialyl(alpha2-6) containing trisaccharides. This suggests a potential future direction for the development of new species-specific antiviral drugs to prevent and treat pandemic flu.
Animals ; Antiviral Agents ; Classification ; Hand ; Humans ; Influenza in Birds ; Influenza, Human* ; Oligosaccharides* ; Oseltamivir* ; Pandemics ; Sensitivity and Specificity ; Trisaccharides

Influenza viruses cause annual epidemics and occasional pandemics that have claimed the millions of lives. On December 4th 2009, more than 207 countries and overseas territories have reported laboratory confirmed cases of pandemic influenza H1N1 2009, which has claimed at least 8768 lives. Up to this date, the pandemic influenza H1N1 2009 has spread throughout the world with unprecedented speed. Accurate and rapid diagnosis of this influenza virus is critical for minimizing further spread, combined with timely implementation of antiviral treatment and public health based measures. Recently, the percentage of oseltamivir-resistant human seasonal H1N1 has increased to 98.5% in USA, and 99.8% in Korea. Fortunately, the pandemic influenza H1N1 2009 is sensitive to neuraminidase inhibitors, including oseltamivir. However, the percentage oseltamivir-resistant pandemic influenza H1N1 2009 is expected to increase with time. In this review, the various diagnostic method and the antiviral agents that have been reported in the literature will be discussed.
Antiviral Agents ; Humans ; Influenza, Human ; Korea ; Neuraminidase ; Orthomyxoviridae ; Oseltamivir ; Pandemics ; Public Health ; Seasons

PURPOSE: We suspect there is a difference in the clinical manifestations and treatment response to antiviral drugs for influenza A and B. This study was conducted to investigate this difference. METHODS: We collected information on pediatric patients, infected with the influenza virus, admitted to Dongguk University Ilsan Hospital from October 2013 to May 2015. We investigated the clinical manifestations of influenza and differences in treatment response to oseltamivir treatment for the two types of influenza. RESULTS: A total of 138 patients were included. The mean age was 3.5±4.0 years. When comparing the diseases associated with influenza A and B, croup (19.2% vs. 1.7%, P=0.001) was more common with influenza A infection. Myositis (0% vs. 6.7%, P=0.021) and gastroenteritis (29.5% vs. 46.7%, P=0.038) were more common with influenza B infection. When comparing the total fever duration from the start of oseltamivir administration, patients treated with oseltamivir within 2 days of fever had the shortest duration. Among the patients treated with oseltamivir, the duration of fever, after the start of oseltamivir treatment, for was shorter for influenza A infection than for influenza B infection (16.0±19.1 hours vs. 28.9±27.9 hours, P=0.006). CONCLUSIONS: There appear to be differences in the accompanying diseases and antiviral medication responses between the two types of influenza. It is important to administer oseltamivir within 2 days of fever.
Antiviral Agents ; Child ; Croup ; Fever ; Gastroenteritis ; Humans ; Influenza, Human* ; Myositis ; Orthomyxoviridae ; Oseltamivir

PURPOSE: Peramivir is the first intravenously administered neuramidase inhibitor for immediate delivery of an effective single-dose treatment in patients with influenza. However, limited data are available on intravenous (IV) peramivir treatment compared to oral oseltamivir for these patients. MATERIALS AND METHODS: With a systematic review and meta-analysis, we compared the efficacy of IV peramivir with oral oseltamivir for treatment of patients with seasonal influenza. MEDLINE, EMBASE, and Cochrane Central Register were searched for relevant clinical trials. RESULTS: A total of seven trials [two randomized controlled trials (RCTs) and five non-randomized observational trials] involving 1676 patients were finally analyzed. The total number of peramivir- and oseltamivir-treated patients was 956 and 720, respectively. Overall, the time to alleviation of fever was lower in the peramivir-treated group compared with the oseltamivir-treated group [mean difference (MD), −7.17 hours; 95% confidence interval (CI) −11.00 to −3.34]. Especially, pooled analysis of observational studies (n=4) and studies of outpatients (n=4) demonstrated the superiority of the peramivir-treated group (MD, -7.83 hours; 95% CI −11.81 to −3.84 and MD, −7.71 hours; 95% CI −11.61 to −3.80, respectively). Mortality, length of hospital stay, change in virus titer 48 hours after admission, and the incidence of adverse events in these patients were not significantly different between the two groups. CONCLUSION: IV peramivir therapy might reduce the time to alleviation of fever in comparison with oral oseltamivir therapy in patients with influenza; however, we could not draw clear conclusions from a meta-analysis because of the few RCTs available and methodological limitations.
Fever ; Humans ; Incidence ; Influenza, Human* ; Length of Stay ; Mortality ; Oseltamivir* ; Outpatients ; Seasons ; Viral Load

Oseltamivir is a potent selective neuraminidase enzyme inhibitor and effective against nearly all strains of influenza A and B. The importance of treating influenza has been recognized, and oseltamivir has been prescribed frequently at the onset of the H1N1 influenza A pandemic this year. However, oseltamivir can cause hemorrhagic colitis as a rare adverse effect. Until now, only two cases of hemorrhagic colitis following the use of oseltamivir have been reported in Japan, and none have been reported in Korea. We report a case of acute hemorrhagic colitis in a 15-year-old boy after the oral administration of oseltamivir for swine originating influenza A.
Administration, Oral ; Adolescent ; Colitis ; Humans ; Influenza, Human ; Japan ; Korea ; Neuraminidase ; Oseltamivir ; Pandemics ; Swine

Acute hemorrhagic leukoencephalopathy is a rare condition associated with the influenza virus, but the role of influenza in this condition has not been clarified. We experienced a patient with influenza A and B virus co-infection who initially presented mild gastrointestinal symptoms and rapidly progressed to coma. Magnetic resonance imaging showed severe brain edema and multiple intracranial hemorrhagic lesions. The patient was treated with oseltamivir and corticosteroid, and her clinical course improved without neurological sequelae.
Brain Edema ; Coinfection* ; Coma ; Herpesvirus 1, Cercopithecine ; Humans ; Influenza, Human* ; Leukoencephalopathies* ; Magnetic Resonance Imaging ; Orthomyxoviridae ; Oseltamivir

Acute hemorrhagic leukoencephalopathy is a rare condition associated with the influenza virus, but the role of influenza in this condition has not been clarified. We experienced a patient with influenza A and B virus co-infection who initially presented mild gastrointestinal symptoms and rapidly progressed to coma. Magnetic resonance imaging showed severe brain edema and multiple intracranial hemorrhagic lesions. The patient was treated with oseltamivir and corticosteroid, and her clinical course improved without neurological sequelae.
Brain Edema ; Coinfection* ; Coma ; Herpesvirus 1, Cercopithecine ; Humans ; Influenza, Human* ; Leukoencephalopathies* ; Magnetic Resonance Imaging ; Orthomyxoviridae ; Oseltamivir