Table 6.

Influenza Antiviral Therapy

Drug	Formulation	Dosing recommendations
		Treatment		Prophylaxisa
		Children	Adults	Children	Adults
Oseltamivir (Tamiflu)	75-mg capsule; 60 mg/5 mL Suspension	≥24 months old: ∼4 mg/kg/day in 2 doses, for a 5-day treatment course	150 mg/day in 2 doses for 5 days	≤15 kg: 30 mg/day; >15 to 23 kg: 45 mg/day; >23 to 40 kg: 60 mg/day; >40 kg: 75 mg/day (once daily in each group)	75 mg/day once daily
		≤15 kg: 60 mg/day; >15 to 23 kg: 90 mg/day; >23 to 40 kg: 120 mg/day; >40 kg: 150 mg/day (divided into 2 doses for each group)
		9–23 months old: 7 mg/kg/day in 2 doses; 0–8 months old: 6 mg/kg/day in 2 doses; premature infants: 2 mg/kg/day in 2 doses		9–23 months old: 3.5 mg/kg once daily; 3–8 months old: 3 mg/kg once daily; not routinely recommended for infants <3 months old owing to limited data in this age group
Zanamivir (Relenza)	5 mg per inhalation, using a Diskhaler	≥7 years old: 2 inhalations (10 mg total per dose), twice daily for 5 days	2 inhalations (10 mg total per dose), twice daily for 5 days	≥5 years old: 2 inhalations (10 mg total per dose), once daily for 10 days	2 inhalations (10 mg total per dose), once daily for 10 days
Amantadine (Symmetrel)b	100-mg tablet; 50 mg/5 mL suspension	1–9 years old: 5–8 mg/kg/day as single daily dose or in 2 doses, not to exceed 150 mg/day; 9–12 years old: 200 mg/day in 2 doses (not studied as single daily dose)	200 mg/day, as single daily dose or in 2 doses	1–9 years old: same as treatment dose; 9–12 years old: same as treatment dose	Same as treatment dose
Rimantadine (Flumadine)b	100-mg tablet; 50 mg/5 mL suspension	Not FDA approved for treatment in children, but published data exist on safety and efficacy in children; suspension: 1–9 years old: 6.6 mg/kg/day (maximum 150 mg/kg/day) in 2 doses; ≥10 years old: 200 mg/day, as single daily dose or in 2 doses	200 mg/day, either as a single daily dose, or divided into 2 doses	FDA approved for prophylaxis down to 12 months of age.1–9 years old: 5 mg/kg/day once daily, not to exceed 150 mg; ≥10 years old: 200 mg/day as single daily dose or in 2 doses	200 mg/day, as single daily dose or in 2 doses

NOTE. Check Centers for Disease Control and Prevention Website (http://www.flu.gov/) for current susceptibility data.

^aIn children for whom prophylaxis is indicated, antiviral drugs should be continued for the duration of known influenza activity in the community because of the potential for repeated and unknown exposures or until immunity can be achieved after immunization.

^bAmantadine and rimantadine should be used for treatment and prophylaxis only in winter seasons during which a majority of influenza A virus strains isolated are adamantine susceptible; the adamantanes should not be used for primary therapy because of the rapid emergence of resistance. However, for patients requiring adamantane therapy, a treatment course of ∼7 days is suggested, or until 24–48 hours after the disappearance of signs and symptoms.