TABLE 4

Recommended Dosage and Schedule of Influenza Antiviral Medications for Treatment and Chemoprophylaxis for the 2011–2012 Influenza Season: United States

MedicationTreatment (5 d)Chemoprophylaxis (10 d)
Oseltamivira
    Adults75 mg twice daily75 mg once daily
    Children >12 mo
    Body weight
        ≤15 kg (≤33 lb)30 mg twice daily30 mg once daily
        >15 to 23 kg (33 to 51 lb)45 mg twice daily45 mg once daily
        >23 to 40 kg (>51 to 88 lb)60 mg twice daily60 mg once daily
        >40 kg (>88 lb)75 mg twice daily75 mg once daily
    Children 3 to <12 mob3 mg/kg per dose twice daily3 mg/kg per dose once per day
    Children 0 to <3 moc3 mg/kg per dose twice dailyNot recommended unless situation judged critical because of limited data on use in this age group
Zanamivird
    Adults10 mg (two 5-mg inhalations) twice daily10 mg (two 5-mg inhalations) once daily
    Children (≥7 y for treatment, 5 y for chemoprophylaxis10 mg (two 5-mg inhalations) twice daily10 mg (two 5-mg inhalations) once daily
  • a Oseltamivir is manufactured by Roche Laboratories (Nutley, NJ) and is administered orally without regard to meals, although administration with meals may improve gastrointestinal tolerability. Oseltamivir is available as Tamiflu in 30-, 45-, and 75-mg capsules and as a powder for oral suspension that is reconstituted to provide a final concentration of 6 mg/mL. The volume of oral suspension is being changed from 12 mg/mL to 6 mg/mL this year to reduce frothing when shaken. Oral suspensions in 12 mg/mL concentrations will remain available until supplies run out. For the 6-mg/mL suspension, a 30-mg dose is given with 5 mL of oral suspension, 45-mg dose is given with 7.5 mL oral suspension, 60-mg dose is given with 10 mL oral suspension, and 75-mg dose is given with 12.5 mL oral suspension. If the commercially manufactured oral suspension is not available, the capsules may be opened and the contents mixed with a sweetened liquid to mask the bitter taste, or a suspension can be compounded by retail pharmacies (final concentration: 15 mg/mL). For patients with renal insufficiency, the dose should be adjusted on the basis of creatinine-clearance rate. For treatment of patients with a creatinine-clearance rate of 10 to 30 mL/min: 75 mg once daily for 5 days. For chemoprophylaxis of patients with a creatinine-clearance rate of 10 to 30 mL/min: 30 mg once daily for 10 days after exposure or 75 mg once every other day for 10 days after exposure (5 doses). (See www.cdc.gov/flu/professionals/antivirals/antiviral-drug-resistance.htm.)

  • b Weight-based dosing is preferred; however, if weight is not known, dosing according to age for treatment (give 2 doses per day) or prophylaxis (give 1 dose per day) of influenza in term infants younger than 1 year may be necessary: 0 to 3 months (treatment only), 12 mg (2 mL of 6 mg/mL commercial suspension); 4 to 5 months, 17 mg (2.8 mL of 6 mg/mL of commercial suspension); 6 to 11 months, 24 mg (4 mL of 6 mg/mL commercial suspension). Although Emergency Use Authorization recommendations for use of oseltamivir in children younger than 1 y expired on June 23, 2010, this drug remains appropriate for use when indicated.

  • c Current weight-based dosing recommendations are not intended for preterm infants. Preterm infants may have slower clearance of oseltamivir because of immature renal function, and doses recommended for term infants may lead to very high drug concentrations in this age group. Limited data from a cohort of preterm infants who received an average dose of 1.7 mg/kg twice daily revealed drug concentrations higher than those observed with the recommended treatment dose in term infants (3 mg/kg twice daily). Observed drug concentrations were highly variable among preterm infants. These data are insufficient to recommend a specific dose of oseltamivir for preterm infants.

  • d Zanamivir is manufactured by GlaxoSmithKline (King of Prussia, PA) and is administered by inhalation using a proprietary “Diskhaler” device distributed together with the medication. Zanamivir is a dry powder (not an aerosol) and should not be administered by using nebulizers, ventilators, or other devices typically used for administering medications in aerosolized solutions. Zanamivir is not recommended for persons with chronic respiratory diseases such as asthma or chronic obstructive pulmonary disease that increase the risk of bronchospasm.

  • Data source: Fiore AE, Fry A, Shay D, Gubareva L, Bresee JS, Uyeki TM; Centers for Disease Control and Prevention. MMWR Recomm Rep. 2011;60(RR-1):1–24.