Side Effects and Safety Information

Who should not take Tamiflu?

Do not take Tamiflu if you are allergic to oseltamivir phosphate or any of the ingredients in Tamiflu.

What should I tell my healthcare provider before taking Tamiflu?

Before you take Tamiflu, tell your healthcare provider if you:

  • Have problems swallowing Tamiflu capsules.
  • Have kidney problems.
  • Have a history of fructose (fruit sugar) intolerance. Tamiflu contains sorbitol and may cause stomach upset and diarrhea in people who are fructose intolerant.
  • Have any other medical conditions.
  • Are pregnant or plan to become pregnant. It is not known if Tamiflu will harm your unborn baby.
  • Are breastfeeding or plan to breastfeed. It is not known if Tamiflu passes into your breast milk. You and your healthcare provider should decide if you will take Tamiflu while you are breastfeeding.

Tell your healthcare provider about all the medicines you take, including prescription or over-the-counter medicines, vitamins, and herbal supplements.

Know the medicines you take. Keep a list of them to show your healthcare provider and pharmacist when you get a new medicine.

How should I take Tamiflu?

  • Take Tamiflu exactly as your healthcare provider tells you to.
  • Take Tamiflu with food or without food. There is less chance of stomach upset if you take Tamiflu with food.
  • If you miss a dose of Tamiflu, take it as soon as you remember. If it is 2 hours or less before your next dose, do not take the missed dose. Take your next dose of Tamiflu at your scheduled time. Do not take 2 doses at the same time.
  • If Tamiflu for Oral Suspension is not available or you cannot swallow Tamiflu capsules, your healthcare provider may instruct you to open Tamiflu capsules and mix the capsules contents with sweetened liquids such as chocolate syrup (regular or sugar-free), corn syrup, caramel topping, or light brown sugar (dissolved in water).
  • If your healthcare provider has instructed you to take Tamiflu for Oral Suspension or open your Tamiflu capsules, read the detailed Instructions for Use.

What are the possible side effects of Tamiflu?

Tamiflu may cause serious side effects, including:

  • Serious skin and allergic reactions. Tamiflu can cause serious skin and allergic reactions. Stop taking Tamiflu and get medical help right away if you get any of the following symptoms:
    • Skin rash or hives
    • Your skin blisters and peels
    • Blisters or sores in your mouth
    • Itching
    • Swelling of your face, eyes, lips, tongue, or throat
    • Trouble breathing
    • Chest pain or tightness
  • Change in behavior. People, especially children, who have the flu can develop nervous system problems and abnormal behavior that can lead to death. During treatment with Tamiflu, tell your healthcare provider right away if you or your child has confusion, speech problems, shaky movements, seizures, or starts hearing voices or seeing things that are not really there (hallucinations).

The most common side effects of Tamiflu when used for treatment of the flu include nausea and vomiting.

The most common side effects of Tamiflu when used for prevention of the flu include nausea, vomiting, diarrhea, and stomach (abdomen) pain.

Tell your healthcare provider if you have any side effect that bothers you or that does not go away.

These are not all the possible side effects of Tamiflu.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1 (800) FDA-1088.

How should I store Tamiflu?

  • Store Tamiflu capsules at room temperature between 68°F to 77°F (20°C to 25°C).
  • Store Tamiflu for Oral Suspension in the refrigerator for up to 17 days between 36ºF to 46ºF (2ºC to 8ºC).
  • Store Tamiflu for Oral Suspension for up to 10 days at room temperature between 68°F to 77°F (20°C to 25°C).
  • Safely throw away any unused Tamiflu that is out of date or no longer needed.

Keep Tamiflu and all medicines out of the reach of children.

General information about the safe and effective use of Tamiflu

Medicines are sometimes prescribed for purposes other than those listed in the Patient Information Guidelines. Do not use Tamiflu for a condition for which it was not prescribed. Do not give Tamiflu to other people, even if they have the same symptoms you have. It may harm them.

If you would like more information, talk with your healthcare provider. You can ask your healthcare provider or pharmacist for information about Tamiflu that is written for health professionals.

Please see the Tamiflu full Prescribing Information for complete safety information.

SAVE $10 on a prescription of Tamiflu

Sign Up for Flu Alerts

Stay ahead of the flu.

Flu Alert

See larger ›

Flu Alert example


Tamiflu is a prescription medicine used to treat the flu (influenza) in people 2 weeks of age and older who have had flu symptoms for no more than 2 days. Tamiflu can also reduce the chance of getting the flu in people 1 year and older.

Tamiflu does not prevent bacterial infections that may happen with the flu.

Tamiflu is not a substitute for an annual flu vaccination.

Do not take Tamiflu if you are allergic to oseltamivir phosphate or any of the ingredients in Tamiflu.

Important Safety Information

  • If you have an allergic reaction or a severe rash with Tamiflu, stop taking it, and contact your doctor right away. This may be very serious.
  • People with the flu, particularly children and adolescents, may be at an increased risk of seizure, confusion, or abnormal behavior early during their illness.
  • Let your doctor know if you are pregnant, nursing, have heart problems, breathing problems, a weakened immune system (immunocompromised), kidney problems or other medical conditions as Tamiflu may not be right for you.
  • Also tell your doctor about any medications you are taking or if you've received a nasal-spray flu vaccine in the past two weeks.
  • The most common side effects are mild to moderate nausea and vomiting, diarrhea and stomach pain.

Please see the Tamiflu full Prescription Information for complete important safety information.

You are encouraged to report side effects to Genentech by calling 1-888-835-2555 or to the FDA by visiting or calling 1-800-FDA-1088.