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Oseltamivir phosphate oral

Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.





This medication is used to treat illness (symptoms) caused by the flu virus (influenza). Oseltamivir is also used to prevent the flu (e.g., in household members exposed to a flu sufferer).

How To Use

Take this medication by mouth as directed by your doctor. You may take it with food or milk to minimize stomach upset. Take it as soon as flu symptoms appear or as soon as possible after you have been exposed (both within 48 hours). Shake the bottle well before each dose. If you have the flu: Take oseltamivir twice a day for 5 days, once in the morning and once in the evening. Complete the entire treatment of 10 doses. To prevent the flu: Take oseltamivir once a day for at least 7 days or take it exactly as prescribed by your doctor. An oral dosing dispenser should be provided with this medication. Measure each dose carefully as indicated on the oral dispenser. If you lose or damage the oral dispenser, use a device (e.g., oral syringe) that will accurately measure 1.25ml (one- quarter teaspoonful) portions. Consult your pharmacist. This medication works best when the amount of medicine in your body is kept at a constant level. Therefore, take this drug at the same time(s) each day. Continue to take this medication until the full-prescribed amount is finished even if symptoms disappear after a few days. Stopping the medication too early may result in a relapse of the infection or may not sufficiently protect you from the flu. Inform your doctor if your condition worsens or if new symptoms appear. If you are uncertain how to use this medication, consult your doctor or pharmacist.

Side Effects

Nausea and vomiting may occur. If any of these effects persist or worsen, notify your doctor. Tell your doctor immediately if any of these serious side effects occur: dizziness, persistent cough. Tell your doctor immediately if any of these unlikely but serious side effects occur: persistent weakness, fever, sore throat. If you notice other effects not listed above, contact your doctor or pharmacist.


Tell your doctor your medical history, especially of: kidney problems, allergies (especially drug allergies). This drug may make you dizzy. Use caution engaging in activities requiring alertness such as driving or using machinery. Limit alcoholic beverages. This medication should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor. It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of all prescription and nonprescription medication you may use. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately.


Do not share this medication with others. Consult your doctor about the risks and important benefits of receiving a yearly flu shot (vaccination) to prevent infection.

Missed Dose

If you miss a dose, use it as soon as you remember. If it is near the time of the next dose (within 2 hours), skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.


Before mixing, store the dry powder at 77 degrees F (25 degrees C). Once mixed, the suspension is good for 10 days and should be refrigerated between 36 and 46 degrees F (2-8 degrees C). Do not freeze.