TAMIFLU is indicated for the treatment of acute, uncomplicated illness due to influenza infection caused by viruses A and B in patients 2 weeks of age and older who have been symptomatic for no more than 2 days, and for prophylaxis of influenza in patients 1 year and older.
Use the dosing reference below to find the right dosage of Tamiflu for your pediatric and adult patients within two days of symptom onset.
*Adapted from the Tamiflu full Prescribing Information
Important Prescribing Information (revised December 2012)
Please prescribe Tamiflu for appropriate patients as follows.
Formulation and concentration or strength:
- Oral suspension (6 mg/mL) or capsules (30 mg, 45 mg or 75 mg).
- Dose: mL (preferred for oral suspension) or mg (preferred for capsules). Please refer to the dosing table for more information.
Frequency and duration:
- Treatment twice daily for 5 days.
- Prophylaxis: once daily, typically for 10 days for postexposure prophylaxis or for up to 6 weeks during community outbreak.
Dosing and administration
Tamiflu may be taken with or without food. However, when taken with food, tolerability may be enhanced in some patients. The recommended oral treatment and prophylaxis dose of Tamiflu is shown in the tables below.
Patients aged 13 years and older should receive Tamiflu 75 mg regardless of weight.
Commonly asked questions by healthcare professionals
What has changed with Tamiflu (oseltamivir phosphate) for Oral Suspension (OS)?
- The concentration of the constituted OS product has changed from 12 mg/mL to 6 mg/mL.
- The oral dispenser is labeled in mL, rather than mg.
- Usable bottle volume has changed from 25 mL to 60 mL.
- The drug product/formulation has not changed.
Why are these changes being made?
The strength of Tamiflu for Oral Suspension helps to reduce the potential for prescribing and dosing confusion through the following:
What if the local pharmacy does not have any Tamiflu for Oral Suspension in stock?
Tamiflu provides the flexibility for healthcare professionals to treat and prevent influenza with alternatives to oral suspension:
- Tamiflu 30-mg or 45-mg capsules, depending on the weight of the child.
- For patients with difficulty swallowing capsules, contents can be mixed into sweetened liquids, such as chocolate syrup, by a caregiver.
In emergency situations, if commercially manufactured Tamiflu for Oral Suspension is not readily available from wholesalers or Genentech, a liquid suspension can be compounded by a pharmacist using Tamiflu 75-mg capsules. Instructions for dosing and compounding may be found in the Tamiflu Prescribing Information.
Taking Tamiflu with other medications1
Information derived from pharmacology and pharmacokinetic studies of oseltamivir suggests that clinically significant drug interactions are unlikely.
Oseltamivir is extensively converted to oseltamivir carboxylate by esterases, located predominantly in the liver.
Drug interactions involving competition for esterases have not been extensively reported in literature. Low protein binding of oseltamivir and oseltamivir carboxylate suggests that the probability of drug displacement interactions is low.
The concurrent use of Tamiflu and live attenuated influenza vaccine (LAIV) intranasal has not been evaluated. However, because of the possibility for interference between these products, LAIV should not be given within 2 weeks before or 48 hours after administration of Tamiflu, unless medically indicated. The concern about possible interference arises from the potential for antiviral drugs to inhibit replication of live virus. Trivalent inactivated influenza vaccine can be administered at any time relative to use of Tamiflu.1
In vitro studies showed no interference with the cytochrome P450 pathway.1
Storing Tamiflu for Oral Suspension
- Refrigeration: stable for 5 weeks (35 days) when stored in a refrigerator at 2° to 8°C (36° to 46°F).
- Room temperature: stable for five days when stored at room temperature, 25°C (77°F).
Storing Constituted Tamiflu for Oral Suspension
- Refrigeration: Stable for up to 17 days when stored in a refrigerator at 2°C to 8°C (36°F to 46°F).
- Room temperature: Stable for up to 10 days when stored at room temperature at 25°C (77°F).
As with all medications, keep out of the reach of children.1 Discard any unused portion when you are finished with your prescribed dosing of Tamiflu.
Important Safety Information
Tamiflu is contraindicated in patients who have had severe allergic reactions such as anaphylaxis or serious skin reactions such as toxic epidermal necrolysis, Stevens-Johnson syndrome, or erythema multiforme to any component of Tamiflu. Cases of these events have been reported in postmarketing experience with Tamiflu. Tamiflu should be stopped and appropriate treatment instituted if an allergic-like reaction occurs or is suspected.
There have been postmarketing reports of delirium and abnormal behavior leading to injury, and in some cases resulting in fatal outcomes, in patients with influenza who were receiving Tamiflu. These events were reported primarily among pediatric patients and often had an abrupt onset and rapid resolution. The contribution of Tamiflu to these events has not been established. Patients with influenza should be closely monitored for signs of abnormal behavior. If neuropsychiatric symptoms occur, the risks and benefits of continuing treatment should be evaluated for each patient.
Serious bacterial infections may begin with influenza-like symptoms or may co-exist with or occur as complications during the course of influenza. Tamiflu has not been shown to prevent such complications.
Efficacy in subjects with chronic cardiac and/or respiratory disease or in immunocompromised patients has not been established. No information is available regarding treatment of influenza in patients at imminent risk of requiring hospitalization.
The concurrent use of Tamiflu with live attenuated influenza vaccine (LAIV) intranasal has not been evaluated. However, because of the potential for interference between these products, LAIV should not be administered within 2 weeks before or 48 hours after administration of Tamiflu, unless medically indicated.
Adverse events that occurred more frequently in patients treated with Tamiflu than in patients taking placebo and occurred in ≥2% of patients were (Tamiflu %, placebo %):
- Treatment in adults - nausea (10%, 6%), vomiting (9%, 3%), bronchitis (2%, 2%)
- Treatment in pediatrics - vomiting (15%, 9%), abdominal pain (5%, 4%), epistaxis (3%, 3%), ear disorder (2%, 1%)
- Prophylaxis of adults - headache (18%, 18%), nausea (7%, 3%), diarrhea (3%, 2%), vomiting (2%, 1%), abdominal pain (2%, 1%)
- Prophylaxis of pediatrics - vomiting (10%, 2%), abdominal pain (3%, 0%), nausea (4%, 1%)
Please see the Tamiflu full Prescribing Information for complete safety information.