Oseltamivir
General Information
Restricted formulary antimicrobial: For details see OUH netFormulary
Adult prescriptions may be authorised as below:
| Flu point of Care or Lab result | Action |
| Flu positive | Oseltamivir can be commenced without Micro/ID advice |
| Flu negative or pending | Discuss prescriptions with Micro/ID |
| No result available | Discuss prescriptions with Micro/ID |
Standard dose
Dose in adults weighing more than 40kg
Treatment: 75mg po BD for 5 days (or 10 days in immunosuppressed patients)
Prophylaxis: 75mg po OD for 10 days
Dose in adults weighing 40kg or less
Treatment: 60mg po BD for 5 days (or 10 days in immunosuppressed patients)
Prophylaxis: 60mg po OD for 10 days
Renal and hepatic impairment
Renal impairment
Use the correct table depending on treatment or prophylaxis. Renal dosing is derived from UKHSA Guidance on use of antiviral agents for the treatment and prophylaxis of seasonal influenza It is acknowledged that some of the advice for renal dosing is different to Renal Drug Database.
Treatment: Recommended oseltamivir treatment dosing in relation to renal function:
| Creatinine Clearance (ml/min) | Oseltamivir PO treatment |
| more than 60 | 75mg BD (For adults weighing 40kg or less: 60mg BD) |
| 31-60 | 30mg BD |
| 11-30 | 30mg OD |
| less than or equal to 10 | 30mg ONCE |
| Haemodialysis (HD) | 30mg ONCE and then 30mg after every HD session |
| Continuous Ambulatory Peritoneal Dialysis (refer to Summary of Product Characteristics for advice in relation to automated peritoneal dialysis [APD] mode) | 30mg ONCE |
|
Haemo(dia)filtration 1-1.8L/hr exchange rate |
30mg OD |
|
Haemo(dia)filtration 1.9 to 3.6L/hr exchange rate |
30mg BD |
|
Haemo(dia)filtration Greater than 3.6L/hr exchange rate |
75mg BD |
Note: Dose ranges use creatinine clearance, rather than eGFR.
Prophylaxis: Recommended oseltamivir prophylaxis dosing in relation to renal function:
| Creatinine Clearance (ml/min) | Oseltamivir PO prophylaxis |
| more than 60 | 75mg OD (For adults weighing 40kg or less: 60mg OD) |
| 31-60 | 30mg OD |
| 11-30 | 30mg every 48 hours |
| less than or equal to 10 | 30mg ONCE, repeated after 7 days |
| Haemodialysis (HD) | 30mg ONCE and then 30mg after every second HD session |
| Continuous Ambulatory Peritoneal Dialysis (refer to Summary of Product Characteristics for advice in relation to automated peritoneal dialysis [APD] mode) | 30mg ONCE, repeated after 7 days |
|
Haemo(dia)filtration 1-1.8L/hr exchange rate |
30mg every 48 hours |
|
Haemo(dia)filtration 1.9 to 3.6L/hr exchange rate |
30mg OD |
|
Haemo(dia)filtration Greater than 3.6L/hr exchange rate |
75mg OD |
Note: Dose ranges use creatinine clearance, rather than eGFR.
Hepatic impairment
No dose adjustment is required either for treatment or for prevention of influenza in patients with hepatic dysfunction.
Pregnancy and breastfeeding
Discuss with pharmacy.
References
- UKHSA (2021) Guidance on use of antiviral agents for the treatment and prophylaxis of seasonal influenza. Version 11. Accessed 15/12/23. LINK
- Roche Products Limited. Tamiflu 75mg Hard Capsules. Summary of Product Characteristics. Last revision of the text 1/1/21. Accessed 15/15/23