Drug action

• Reduced replication of influenza A and B viruses by inhibiting viral neuraminidase

Indication

• Post-exposure prophylaxis of influenza
• By mouth (adult over 41kg): 75mg once daily for 10 days for post-exposure prophylaxis, up to 6 weeks during an epidemic
• Treatment of influenza
• By mouth (adult over 41kg): 75mg twice daily for 5 days

Side effects

• Dizziness, gastrointestinal discomfort, herpes simplex, nausea, sleep disorders, vertigo, vomiting
• Arrhythmia, impaired consciousness, seizure, skin reactions
• Angiodema, anxiety, confusion, delirium, delusions

Suitability

• Pregnancy: can be used when benefit > risk
• Breast feeding: benefit > risk, preferred drug

Reference

1. NICE (n.d.). Oseltamivir. [online] NICE. Available at: https://bnf.nice.org.uk/drugs/oseltamivir/ [Accessed 3 Nov. 2026].