II. Indications
-
Influenza
- Alternative to Oseltamivir (Tamiflu)
III. Mechanism
IV. Dosing
- One single oral dose for over age 12 years
- Weight 88 to 176 lb (40 to 80 kg): 40 mg (two 20 mg tablets)
- Weight >176 lb (>80 kg): 80 mg (two 40 mg tablets)
- Costs $155 in 2019 (contrast with $50-75 for Tamiflu)
V. Efficacy
- May shorten Influenza symptoms by up to 1 day if started within 48 hours
- No evidence for benefit in high risk patients (under age 2, over age 65, pregnancy)
- Appears effective for Influenza Prophlaxis (but not FDA approved for prophylaxis as of 2020)
- Single dose after household exposure may prevent up to 1 case in 9 contacts
- Ikematsu (2020) N Engl J Med 383:309-20 [PubMed]
VI. Adverse Effects (in 1-3% of patients)
VII. Drug Interactions
- Agents that decrease absorption (e.g. calcium including dairy products, aluminum, Magnesium or iron salts)
VIII. References
- (2020) Presc Lett 27(10): 55-6
- (2018) Presc Lett 25(12): 67
- Erlich (2019) Am Fam Physician 100(12): 776-7 [PubMed]