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  5. Tamiflu: Consumer Questions and Answers
  1. Postmarket Drug Safety Information for Patients and Providers

Tamiflu: Consumer Questions and Answers

Q.  What is Tamiflu and what is it approved for?

A. Tamiflu (oseltamivir phosphate) is an antiviral drug.  It works by attacking the flu virus to keep it from multiplying in your body and by reducing the symptoms of the flu. Tamiflu can sometimes keep you from getting the flu if you take it before you get sick.

The term "flu" refers to illness caused by the influenza virus. The flu is a respiratory infection that can cause symptoms such as fever, chills, aches and pains, cough, and sore throat. The flu can range from mild common cold symptoms, to the typical "flu" symptoms described above, to life-threatening pneumonia and other complications, including secondary bacterial infections.

Tamiflu is used to treat people 2 weeks of age and older who have the flu (influenza A and B viruses). Tamiflu is also sometimes used for prevention (prophylaxis) of the flu in people 1 year of age and older, but it is not a substitute for getting the flu vaccine.

Q. Is Tamiflu a substitute for the flu vaccine?

A. No.  Getting the flu vaccine is the best way to protect against getting the flu and to control the spread of the flu.

Other important parts of avoiding flu include avoiding unnecessary close contact between sick and well people, covering coughs and sneezes, and washing hands frequently.

More information on flu vaccines and other flu control measures is available on the Flu.gov website.

Q. What do the terms treatment of the flu and prevention (prophylaxis) of the flu mean? 

A. Treatment is used when a person is given Tamiflu because they have the signs and symptoms of the flu or have been diagnosed with the flu. Tamiflu has been shown to lessen the amount of time people are sick with the flu.

Prevention (prophylaxis) is a term used when someone who does not have flu symptoms is given Tamiflu to help stop them from getting the flu because they are exposed to or come into close contact with someone (for example live with or take care of someone) who has the flu.

Q. Do I take Tamiflu the same way for treatment and prevention (prophylaxis) of the flu?

A. No. The number of times a day (frequency) and the number of days (duration) that you take Tamiflu are different for treatment and prevention of the flu. Your healthcare provider will tell you how to take Tamiflu. Take it exactly as your healthcare provider prescribes.

Q. What should people do if they continue to have or start to develop flu symptoms while taking Tamiflu?

A. If flu symptoms do not go away, or if new symptoms develop while taking Tamiflu, people should contact their healthcare provider. Other illnesses may cause people to have symptoms similar to the flu, or may occur at the same time as the flu, and they might need other treatment.

Q. Does Tamiflu come in a liquid as well as capsules?

A. Yes, Tamiflu is available as a liquid (oral suspension) and as oral capsules of different sizes. Your healthcare provider will prescribe the strength that is right for you.

Q. Do I need to make the Tamiflu liquid (oral suspension)?

A. No, a pharmacist should mix Tamiflu liquid before giving it to you.  If you get a bottle with only powder in it, you should return the medication to the pharmacy so it can be mixed correctly.

Q. Is there enough Tamiflu suspension?

A. At some times there might not be enough of the pre-packaged liquid Tamiflu made by the manufacturer.  Some pharmacies may need to make a liquid for patients from the pills instead.  You should always follow the directions on the medicine label for how much and how often to give the medication.  You should speak with your healthcare provider if you have any questions.

Q.  Does the liquid (oral suspension) need to be refrigerated?

A. Yes, liquid Tamiflu (oral suspension) should be stored in the refrigerator. Ask the pharmacist how long to keep the medicine, and then throw away the unused medicine after that time. You should only use the medication for as long as your healthcare provider has directed.

Q. Does liquid Tamiflu (oral suspensions) need to be shaken? 

A. Yes, shake liquid Tamiflu well each time before you give it.

Q. What do I use to give liquid Tamiflu (oral suspension)? 

A. The pharmacist should give you a syringe to measure the dose of liquid Tamiflu.  You and your pharmacist should look at the syringe and compare it to the directions on the medicine label. You should be able to use the syringe to measure the right amount that is written on the medicine label.    If you have any questions about whether the measurements on the syringe, the medication label, and the prescription are all the same, make sure that you and your pharmacist and your doctor have answered those questions before you use the Tamiflu.

Q. What should I do if I am given Tamiflu capsules but can not swallow them?

A. If you have trouble swallowing Tamiflu capsules, you should tell your healthcare provider.  Adults and children 1 year of age and older can be correctly dosed with capsules even if they can not swallow the capsules.  If liquid Tamiflu is not available and you have capsules that give the right dose (30 mg, 45 mg or 75 mg), you may pull open the Tamiflu capsules and mix the powder with a small amount of sweetened liquid such as regular or sugar-free chocolate syrup. You don’t have to use chocolate syrup but thick, sweet liquids work best at covering up the taste of the medicine.

Q. Should women who are pregnant or nursing take Tamiflu?

A. Tamiflu may be of benefit for some pregnant and nursing women. At this time, the U.S. Centers for Disease Control and Prevention (CDC) recommends that pregnant women who are sick from influenza should be treated with a flu drug because of concerns that they could develop more severe illness.   Pregnant and nursing women are advised to talk with a healthcare professional before using Tamiflu.

More information is available at flu.gov.

Q. What are the most common side effects of Tamiflu?

A. The most common side effects of Tamiflu are nausea and vomiting. Usually, nausea and vomiting are not severe and happen in the first 2 days of treatment. Taking Tamiflu with food may lessen the chance of getting these side effects. Other side effects include stomach (abdominal) pain, nosebleeds, headache, and feeling tired (fatigue).

Q. What are the serious side effects of Tamiflu?

A. Children and teenagers with the flu may be at a higher risk for seizures, confusion, or abnormal behavior early during their illness. These serious side effects may happen shortly after beginning Tamiflu or may happen in people when the flu is not treated. These serious side effects are not common but may result in accidental injury to the patient. People who take Tamiflu should be watched for signs of unusual behavior and a healthcare provider should be contacted right away if the patient shows any unusual behavior while taking Tamiflu.

Rare cases of allergic reactions, including serious skin rashes, have happened in people who take Tamiflu. If a rash develops, stop taking Tamiflu and contact a healthcare provider right away.

FDA encourages consumers to report any side effects and medication errors from Tamiflu to FDA at 1-800-FDA-1088. 

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