Tamiflu

Generic Name: oseltamivir (os el TAM ih veer)
Brand Name: Tamiflu

What is Tamiflu?

Tamiflu (oseltamivir) is an antiviral medication that blocks the actions of influenza virus types A and B in your body.

Tamiflu is used to treat flu symptoms caused by influenza virus in patients who have had symptoms for less than 2 days. Tamiflu may also be given to prevent influenza in people who may be exposed but do not yet have symptoms. It will not treat the common cold.

Tamiflu may also be used for purposes not listed in this medication guide.

Important information about Tamiflu

Tamiflu is used to treat flu symptoms caused by influenza virus in patients who have had symptoms for less than 2 days. Tamiflu may also be given to prevent influenza in people who may be exposed but do not yet have symptoms. This medicine will not treat the common cold.

Before taking this medicine, tell your doctor if you have received a nasal flu vaccine within the past 2 weeks, or if you have kidney disease, heart disease, lung disease, or any other serious disease or health problem. Also tell your doctor if you have any condition causing swelling or disorder of the brain.

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Treatment with Tamiflu should start as soon as possible when flu symptoms appear, such as fever, chills, muscle aches, sore throat, and runny or stuffy nose.

Take this medication for as many days as it has been prescribed for you even if you begin to feel better. Your symptoms may start to improve before the infection is completely treated. Some people using Tamiflu have had rare side effects of sudden confusion, delirium, hallucinations, unusual behavior, or self-injury. These symptoms have occurred most often in children. It is not known whether oseltamivir was the exact cause of these symptoms. However, anyone using Tamiflu should be watched closely for signs of confusion or unusual behavior. Call a doctor at once if you or the child has any of these symptoms.

Tamiflu should not be used in place of getting a yearly flu shot. The Centers for Disease Control recommends an annual flu shot to help protect you each year from new strains of influenza virus.

It is dangerous to purchase medicines on the Internet or from vendors outside of the United States. Samples of "Tamiflu" purchased on the Internet have been found to contain cloxacillin, a type of antibiotic that can have dangerous side effects in people who are allergic to penicillin.

Before using Tamiflu

Tamiflu should not be used in place of getting a yearly flu shot. The Centers for Disease Control recommends an annual flu shot to help protect you each year from new strains of influenza virus.

You should not use Tamiflu if you are allergic to oseltamivir.

To make sure you can safely take Tamiflu, tell your doctor if you have other medical conditions, especially:

• kidney disease;

• heart disease;

• lung disease;

• a condition causing swelling or disorder of the brain;

• any other serious disease or health problem; or

• if you have used a nasal flu vaccine (FluMist) within the past 2 weeks.

FDA pregnancy category C. It is not known whether Tamiflu is harmful to an unborn baby. However, not receiving this medication to prevent influenza could be harmful to the baby if the mother becomes infected with a disease that Tamiflu could prevent. Before taking this medication, tell your doctor if you are pregnant. Your doctor will decide whether you should receive this medicine, especially if you have a high risk of infection with H1N1 influenza (also called "swine" flu).

See also: Tamiflu pregnancy and breastfeeding warnings (in more detail)

It is not known whether oseltamivir passes into breast milk or if it could harm a nursing baby. Do not take Tamiflu without telling your doctor if you are breast-feeding a baby. Do not give this medication to infants younger than 2 weeks old.

How should I take Tamiflu?

Take Tamiflu exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

Treatment with Tamiflu should start as soon as possible when flu symptoms appear, such as fever, chills, muscle aches, sore throat, and runny or stuffy nose.

Take the Tamiflu capsule with a full glass of water. Shake the oral suspension (liquid) well just before you measure a dose. Measure the liquid with a special dose-measuring spoon or medicine cup, not with a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist for one.

Tamiflu may be taken with food or milk if it upsets your stomach.

To treat flu symptoms: Take every 12 hours for 5 days.

To prevent flu symptoms: Take every 24 hours for 10 days or as prescribed. Follow your doctor's instructions.

Use this medication for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated. Tell your doctor if your symptoms do not improve, or if they get worse.

Store Tamiflu capsules at room temperature away from moisture and heat. Store the liquid medicine in the refrigerator but do not freeze. Throw away any unused liquid after 10 days.

See also: Tamiflu dosage (in more detail)

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if your next dose is less than 2 hours away. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include nausea and vomiting.

What should I avoid while taking Tamiflu?

Do not use a nasal flu vaccine (FluMist) within 48 hours after taking Tamiflu. Oseltamivir may interfere with the drug action of FluMist, making the vaccine less effective. Follow your doctor's instructions.

Tamiflu side effects

Stop using this medicine and get emergency medical help if you have any of these signs of an allergic reaction to Tamiflu: hives; difficulty breathing; swelling of your face, lips, tongue, or throat; a red and blistering or peeling skin rash. Some people using Tamiflu have had rare side effects of sudden confusion, delirium, hallucinations, unusual behavior, or self-injury. These symptoms have occurred most often in children. It is not known whether oseltamivir was the exact cause of these symptoms. However, anyone using this medicine should be watched closely for signs of confusion or unusual behavior.

Call a doctor at once if you or the child using Tamiflu has any of these symptoms.

Less serious Tamiflu side effects may include:

• nausea, vomiting, diarrhea;

• dizziness, headache;

• nosebleed;

• eye redness or discomfort;

• sleep problems (insomnia); or

• cough or other respiratory symptoms.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Tamiflu side effects (in more detail)

What other drugs will affect Tamiflu?

There may be other drugs that can interact with Tamiflu. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

Where can I get more information?

• Your pharmacist can provide more information about Tamiflu.