Drug	Type of influenza	Adult dosage*	Rate of discontinuation (%)†	Cost per course‡
Amantadine (Symmetrel)	A	100 mg orally twice per day	15	$14.62 ($9.73 to 13.62 generic)
Rimantadine (Flumadine)	A	100 mg orally twice per day	6	22.88
Zanamivir (Relenza)	A, B	10 mg inhaled twice per day	3	60.04
Oseltamivir (Tamiflu)	A, B	75 mg orally twice per day	3	73.54