Oseltamivir

This form:

Pronounced

"oss-el-TAM-eh-veer"

Common brand names:

Tamiflu

Uses

Oseltamivir is used to treat symptoms caused by the flu virus (influenza). It helps make the symptoms (such as stuffy nose, cough, sore throat, fever/chills, aches, tiredness) less severe and shortens the recovery time by 1-2 days.

This medication may also be used to prevent the flu if you have been exposed to someone who already has the flu (such as a sick household member) or if there is a flu outbreak in the community. Talk to your doctor for more details.

This medication works by stopping the flu virus from growing. It is not a substitute for the flu vaccine. (See also Notes section.)

How to Use This Medication

Read the Patient Information Leaflet if available from your pharmacist before you start taking this medicine. If you have any questions, consult your doctor or pharmacist.

Take this medication by mouth with or without food. You may take it with food or milk to minimize stomach upset. Take this medication as soon as flu symptoms appear or as soon as possible after you have been exposed to the flu. Oseltamivir works best if you start taking it within 2 days of either of these events.

If you have the flu, take oseltamivir as directed by your doctor, usually twice a day for 5 days.

To prevent the flu, take oseltamivir as directed by your doctor, usually once a day for at least 10 days. Follow your doctor's instructions for how long to take this medicine.

The dosage is based on your medical condition and response to treatment. Children's dosage is also based on weight.

If you cannot swallow the capsules, ask your doctor or pharmacist about the liquid suspension form of oseltamivir. If the liquid is not available and if directed by your doctor or pharmacist, you may open up the capsule and mix the contents with a small amount of sweetened liquid (such as regular/sugar-free chocolate syrup, corn syrup, caramel topping, or light brown sugar dissolved in water). Stir the mixture and take the entire dose.

For the best effect, take this medication at evenly spaced times. To help you remember, take this medication at the same time(s) every day. Continue to take this medication for the full time prescribed, even if symptoms disappear after a few days. Stopping the medication too early may result in a return of the infection or failure to protect you from the flu.

Tell your doctor if your condition lasts or gets worse or if new symptoms appear.

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Information expires December 2025.