Tamiflu Prophylaxis in Adults with Household Exposure to Influenza

Standard Adult Prophylaxis Dosing

The FDA-approved dose for post-exposure prophylaxis in adults is 75 mg once daily for at least 10 days following close contact with an infected individual, according to the Pediatrics guideline 1, 2
This dosing applies specifically to household exposure settings where you have identified contact with a confirmed or suspected influenza case, as recommended by Pediatrics and Praxis Medical Insights 1, 2
The medication can be taken with or without food, though taking it with meals may reduce gastrointestinal side effects like nausea, as noted by Pediatrics and Praxis Medical Insights 1, 2

Oseltamivir is available as 75 mg capsules or as oral suspension at 6 mg/mL concentration, as stated by Pediatrics and Praxis Medical Insights 1, 2
If capsules cannot be swallowed, they can be opened and mixed with liquid, or the oral suspension can be used, according to Praxis Medical Insights 2

For creatinine clearance 10-30 mL/min, reduce to 30 mg once daily for 10 days OR 75 mg every other day for 10 days, as recommended by Pediatrics and Praxis Medical Insights 1, 2

Do not delay initiation waiting for laboratory confirmation of influenza in the index case—start prophylaxis based on clinical suspicion if within the 48-hour window, as advised by Praxis Medical Insights 2
Do not confuse prophylaxis dosing with treatment dosing, as this is a common prescribing error, according to Pediatrics 1
If the patient received live attenuated influenza vaccine within the past 2 weeks, avoid oseltamivir as it may interfere with vaccine efficacy, as noted by Praxis Medical Insights 2