[Oseltamivir photo]
KEY POINTS
- Oseltamivir (Tamiflu) is a neuraminidase inhibitor that works by blocking influenza neuraminidase, which is an enzyme involved in viral replication
- Used for prophylaxis or treatment of influenza virus A or B
- Cross-resistance has been observed amongst the neuraminidase inhibitors and can vary by virus strain
- Adjust doses for renal function
- Typical prophylaxis regimen in adults is 75mg daily for 7 or 10 days
- For institutional outbreaks may be given for a greater duration
- Should be started within 48 hours of contact with infected person
- Typic treatment regimen in adults is 75mg twice daily for 5 days
- In severe or complicated infections may be given for a greater duration
- Should be started within 48 hours of symptom onset
- Weight-based dosing is used in pediatrics
- Dosing in critically ill or obese patients is still debated, but it seems dosage adjustments for either of these populations is unnecessary
- Only available oral in the United States as capsule or solution
- Some side effects to beware includes: neuropsychiatric events, headache, vomiting, and nausea
- Pregnancy category C
RESOURCES
- Oseltamivir Package Insert
- CDC Guidance on the Use of Influenza Antiviral Agents
- CDC Tables on the Recommended Dosage and Duration of Influenza Antiviral Medications for Treatment or Chemoprophylaxis
- Antimicrobial stewardship for hospitalized patients with viral respiratory tract infections (2017)
- Global update on the susceptibility of human influenza viruses to neuraminidase inhibitors, 2013-2014 (2015)
- Influenza neuraminidase inhibitors: antiviral action and mechanisms of resistance (2013)