Skip to Content

Oseltamivir Dosage

Applies to the following strength(s): 75 mg ; 45 mg ; 30 mg ; 12 mg/mL ; 6 mg/mL

The information at Drugs.com is not a substitute for medical advice. ALWAYS consult your doctor or pharmacist.

Usual Adult Dose for:

Usual Pediatric Dose for:

Additional dosage information:

Usual Adult Dose for Influenza

75 mg orally twice a day for 5 days

Use: For the treatment of acute, uncomplicated influenza infection in patients symptomatic no more than 48 hours

Usual Adult Dose for Influenza Prophylaxis

After close contact with an infected individual: 75 mg orally once a day for at least 10 days
During a community outbreak of influenza: 75 mg orally once a day

Comments:
-Therapy should begin within 48 hours of exposure.
-Safety and efficacy have been established for up to 6 weeks in immunocompetent patients; duration of protection lasts as long as dosing is continued.
-Safety has been established for up to 12 weeks in immunocompromised patients.

Usual Pediatric Dose for Influenza

2 weeks to less than 1 year: 3 mg/kg orally twice a day

1 to 12 years:
15 kg or less: 30 mg orally twice a day
15.1 through 23 kg: 45 mg orally twice a day
23.1 through 40 kg: 60 mg orally twice a day
40.1 kg or more: 75 mg orally twice a day

13 years or older: 75 mg orally twice a day

Duration of therapy: 5 days

Comments:
-For patients younger than 1 year, an appropriate dosing device that can accurately measure and administer small volumes should be provided.

Use: For the treatment of acute, uncomplicated influenza infection in patients (2 weeks or older) symptomatic no more than 48 hours

US CDC and American Academy of Pediatrics (AAP) Recommendations:
Preterm infants:
Postmenstrual age less than 38 weeks: 1 mg/kg orally twice a day
Postmenstrual age 38 through 40 weeks: 1.5 mg/kg orally twice a day
Postmenstrual age greater than 40 weeks: 3 mg/kg orally twice a day

Full-term infants 8 months or younger: 3 mg/kg orally twice a day
Infants 9 to 11 months: 3.5 mg/kg orally twice a day

Children 12 months or older:
15 kg or less: 30 mg orally twice a day
Greater than 15 to 23 kg: 45 mg orally twice a day
Greater than 23 to 40 kg: 60 mg orally twice a day
Greater than 40 kg: 75 mg orally twice a day

Comments:
-A pediatric infectious disease specialist should be consulted for extremely premature infants (postmenstrual age less than 28 weeks).

Usual Pediatric Dose for Influenza Prophylaxis

1 to 12 years:
15 kg or less: 30 mg orally once a day
15.1 through 23 kg: 45 mg orally once a day
23.1 through 40 kg: 60 mg orally once a day
40.1 kg or more: 75 mg orally once a day

13 years or older: 75 mg orally once a day

Duration of therapy:
-After close contact with an infected individual: 10 days
-During a community outbreak of influenza: May be continued for up to 6 weeks

Comments:
-Therapy should begin within 48 hours of exposure.
-The US FDA has not approved this use for patients younger than 1 year.

US CDC and AAP Recommendations:
Full-term infants younger than 3 months: Not recommended unless situation judged critical.
Full-term infants 3 to 8 months: 3 mg/kg orally once a day
Infants 9 to 11 months: 3.5 mg/kg orally once a day

Children 12 months or older:
15 kg or less: 30 mg orally once a day
Greater than 15 to 23 kg: 45 mg orally once a day
Greater than 23 to 40 kg: 60 mg orally once a day
Greater than 40 kg: 75 mg orally once a day

Renal Dose Adjustments

Adults:
Influenza Treatment:
-Mild renal dysfunction (CrCl greater than 60 to 90 mL/min): 75 mg orally twice a day
-Moderate renal dysfunction (CrCl greater than 30 to 60 mL/min: 30 mg orally twice a day
-Severe renal dysfunction (CrCl greater than 10 to 30 mL/min): 30 mg orally once a day
-ESRD not on dialysis (CrCl 10 mL/min or less): Not recommended.

Duration of therapy: 5 days

Influenza Prophylaxis:
-Mild renal dysfunction (CrCl greater than 60 to 90 mL/min): 75 mg orally once a day
-Moderate renal dysfunction (CrCl greater than 30 to 60 mL/min: 30 mg orally once a day
-Severe renal dysfunction (CrCl greater than 10 to 30 mL/min): 30 mg orally every other day
-ESRD not on dialysis (CrCl 10 mL/min or less): Not recommended.

Duration of prophylaxis: Same as recommended with normal renal function

Liver Dose Adjustments

Mild to moderate liver dysfunction (Child-Pugh score 9 or less): No adjustment recommended.
Severe liver dysfunction: Data not available

Precautions

Safety and efficacy for treatment of influenza have not been established in patients younger than 2 weeks. Safety and efficacy for prophylaxis of influenza have not been established in patients younger than 1 year.

Consult WARNINGS section for additional precautions.

Dialysis

Adults:
Influenza Treatment:
-ESRD on hemodialysis (CrCl 10 mL/min or less): 30 mg orally after each hemodialysis cycle
-ESRD on CAPD (CrCl 10 mL/min or less): 30 mg orally as a single dose immediately after a dialysis exchange

Duration of therapy: Should not exceed 5 days, assuming 3 hemodialysis sessions are performed in the 5-day period

Comments: Treatment can be started immediately if influenza symptoms develop during the 48 hours between hemodialysis sessions; however, the post-hemodialysis dose should still be administered independently of time of initial dose administration.

Influenza Prophylaxis:
-ESRD on hemodialysis (CrCl 10 mL/min or less): 30 mg orally after alternate hemodialysis cycles
-ESRD on CAPD (CrCl 10 mL/min or less): 30 mg orally once a week immediately after dialysis exchange

Duration of prophylaxis: Same as recommended with normal renal function

Comments: An initial dose can be administered before the start of hemodialysis.

Other Comments

Administration advice:
-Start therapy within 48 hours of onset of influenza symptoms or after close contact with an infected individual.
-May administer without regard to food; administration with food may improve tolerability in some patients.
-The oral suspension is preferred for patients unable to swallow capsules; use an oral dosing device that measures the appropriate volume in mL.
-Shake the oral suspension (commercial or emergency compounded) well before each use; discard unused portions after the completion of therapy.
-Consult the manufacturer product information regarding missed doses.

Storage requirements:
-Constituted oral suspension: Store under refrigeration for up to 17 days at 2C to 8 C (36F to 46F), freezing should be avoided; or store for up to 10 days at controlled room temperature, 25C (77F) with excursions permitted to 15C to 30C (59F to 86F).
-Emergency compounded oral suspension: Stable for 35 days when stored refrigerated at 2C to 8 C (36F to 46F) or 5 days when stored at room temperature, 25C (77F).

Reconstitution/preparation techniques:
-The manufacturer product information should be consulted for preparation of the oral suspension; it should be constituted by the pharmacist prior to dispensing to the patient.
-If the oral suspension is unavailable: The capsules may be opened and mixed with sweetened liquids such as chocolate syrup (regular or sugar-free), corn syrup, caramel topping, or light brown sugar (dissolved in water).
-If the appropriate capsule strengths are not available to mix with sweetened liquids and the oral suspension is unavailable: An emergency supply of oral suspension may be compounded from the 75 mg capsules.

During emergency situations only:
-If commercially manufactured oral suspension is not available, emergency compounded oral suspension (6 mg/mL), enough for 1 patient's treatment for 5 days or prophylaxis for 10 days, may be prepared from the 75 mg capsules as follows:
1. Determine the dose of oseltamivir for the patient then determine the total volume of oral suspension necessary to be compounded; if the dose is between listed doses, total volume of oral suspension to compound should default to the next greater dose listed.
-Dose of 15 mg or less: 37.5 mL total volume
-Dose of 30 mg: 75 mL total volume
-Dose of 45 mg: 100 mL total volume
-Dose of 60 mg: 125 mL total volume
-Dose of 75 mg: 150 mL total volume

2. Determine the number of 75 mg capsules (includes overage to ensure delivery of all doses), amount of water, and amount of vehicle (Cherry Syrup, Ora-Sweet[R] SF, or simple syrup) necessary to prepare the total volume of compounded oral suspension (6 mg/mL).
-Total volume of 37.5 mL: 3 capsules (225 mg oseltamivir) plus 2.5 mL water plus 34.5 mL vehicle
-Total volume of 75 mL: 6 capsules (450 mg oseltamivir) plus 5 mL water plus 69 mL vehicle
-Total volume of 100 mL: 8 capsules (600 mg oseltamivir) plus 7 mL water plus 91 mL vehicle
-Total volume of 125 mL: 10 capsules (750 mg oseltamivir) plus 8 mL water plus 115 mL vehicle
-Total volume of 150 mL: 12 capsules (900 mg oseltamivir) plus 10 mL water plus 137 mL vehicle

3. The procedure below should be followed to compound the oral suspension (6 mg/mL) from 75 mg capsules:
(a) Place the specified amount of water into a polyethyleneterephthalate (PET) or glass bottle.
(b) Carefully separate the capsule body and cap and place the contents of the number of 75 mg capsules needed into the PET or glass bottle.
(c) Gently swirl the suspension to ensure adequate wetting of the oseltamivir powder for at least 2 minutes.
(d) Slowly add the specified amount of vehicle to the bottle.
(e) Use a child-resistant cap to close the bottle and shake well for 30 seconds to completely dissolve the active drug and to ensure homogeneous distribution of the dissolved drug in the resulting suspension; the active drug (oseltamivir phosphate) is soluble in the specified vehicles but some of the inert ingredients are insoluble, causing the suspension.

General:
-Efficacy has not been established in patients starting therapy after 48 hours of symptoms.
-This drug is not a substitute for annual, early influenza vaccination as recommended by the US CDC Advisory Committee on Immunization Practices.
-Efficacy has not been established for any illness due to agents other than influenza viruses types A and B.
-As influenza viruses change over time, resistant or more virulent mutations may emerge and decrease the efficacy of antiviral drugs; available influenza drug susceptibility patterns and treatment effects should be considered when deciding whether to use this drug.
-The sorbitol content in one 75 mg dose of the oral suspension is 2 g, which exceeds the daily maximum limit for patients with hereditary fructose intolerance.

Monitoring:
-Psychiatric: For signs of abnormal behavior in patients with influenza

Hide