Drug factors		Oseltamivir (Tamiflu)		Zanamivir (Relenza)
Generic availability		No		No
Dosage forms		Liquid and capsule		Powder for oral inhalation
Treatment of influenza types A and B in adults		Yes		Yes
Treatment of influenza types A and B in children		Yes, in children > one year of age		Yes, in children seven years of age
Prevention of influenza types A and B in adults		Yes		FDA approval pending
Prevention of influenza types A and B in children		Yes, in children 13 years of age		FDA approval pending
Dosage for treatment of influenza types A and B*		Adults and children 13 years: 75 mg twice daily for five days		Two inhalations (10 mg) twice daily for five days
		Children one to 12 years (following doses are given twice daily for five days):
			15 kg (33 lb) or less: 30 mg
			15 kg to 23 kg (51 lb): 45 mg
			23 kg to 40 kg (88 lb): 60 mg
			> 40 kg: 75 mg
Dosage for prevention of influenza types A and B		Adults and children 13 years: 75 mg once daily for at least seven days†		Approval pending. Two inhalations (10 mg) once daily for at least seven days†
Dosage reduction in renal impairment		Yes (creatinine clearance 30 mL per minute [0.5 mL per second])		No
Side effects		GI		Minimal
Cost‡
	Five-day treatment (adult dosage)	$63		$50
	42-day treatment (adult dosage in community outbreaks)	$265		$212 (approval pending)
Precautions		Take with food to improve tolerance		Not recommended in patients with asthma or COPD
		Suspension should be shaken before each use and is stable at room temperature for 10 days
				May cause bronchospasm