Oseltamivir

Oseltamivir is a prescription medication used to prevent and treat "the flu", an infection caused by the influenza virus. Oseltamivir belongs to a group of drugs called neuraminidase inhibitors, which attack the influenza virus to stop it from spreading inside your body.

This medication comes in capsule and suspension (liquid) forms and is usually taken once or twice a day, with or without food.

Common side effects include nausea and vomiting.

Oseltamivir is a prescription medication used to prevent and treat "the flu", an infection caused by the influenza virus. It is approved to treat adults and children ages 2 weeks and older who have shown symptoms of flu for no longer than two days, and to prevent flu in adults and children ages 1 year and older. 

Flu symptoms include:

• fever (usually 100ºF to 103ºF in adults, and sometimes higher in children) 
• cough
• sore throat
• runny or stuffy nose
• headaches
• muscle aches
• extreme tiredness

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Oseltamivir may be found in some form under the following brand names:

• Tamiflu

The most common side effects of oseltamivir are mild to moderate nausea and vomiting,usually during the first 2 days of treatment. Taking oseltamivir with food may reduce the chance of getting these side effects.

If you develop an allergic reaction or severe rash, stop taking oseltamivir and contact your healthcare professional.

People with the flu, particularly children and adolescents, may be at an increased risk of:

• seizures
• confusion
• abnormal behavior early during their illness.

These events may occur shortly after beginning oseltamivir or may occur when flu is not treated. These events are uncommon but may result in accidental injury to the patient. Therefore, patients should be observed for signs of unusual behavior and a healthcare professional should be contacted immediately if the patient shows any signs of unusual behavior.

Tell your doctor about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. 

Before taking oseltamivir, please let your healthcare provider know if you have received nasally administered influenza virus vaccine during the past two weeks. It is possible that oseltamivir will make the vaccine less effective. 

Do not take oseltamivir if you are allergic to any ingredients in it.

Before starting treatment, make sure your healthcare professional knows if you:

• take any other medicines
• are pregnant or planning to become pregnant
• are breastfeeding

Oseltamivir is normally not recommended for use during pregnancy or nursing, as the effects on the unborn child or nursing infant are unknown. Oseltamivir is not recommended for use in children younger than 2 weeks of age.

Tell your healthcare professional if you have any type of kidney disease, heart disease, respiratory disease, or any serious health condition.

Oseltamivir for oral suspension may contain sorbitol. Sorbitol may cause upset stomach and diarrhea in patients with a family history of fructose intolerance.

Medicines can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of oseltamivir there are no specific foods that you must exclude from your diet when receiving this medication.

Tell your healthcare provider if you are allergic to any ingredient in oseltamivir.

Before starting treatment, make sure your healthcare professional knows if you:

• have kidney disease
• have heart disease
• have lung disease
• have any other serious health condition 
• are pregnant, planning to become pregnant, or breastfeeding. Oseltamivir is normally not recommended for use during pregnancy or nursing, as the effects on the unborn child or nursing infant are unknown. Oseltamivir is not recommended for use in children younger than 2 weeks of age.

Tell your healthcare provider about all the medicines you take including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you have received nasally administered influenza virus vaccine during the past two weeks.

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

This medication falls into category C. There are no well-controlled studies that have been done in pregnant women. Oseltamivir should be used during pregnancy only if the possible benefit outweighs the possible risk to the unborn baby.

Tell your doctor if you are breastfeeding or plan to breastfeed. It is not known if oseltamivir is excreted in human breast milk or if it will harm your nursing baby.

It is important that you begin your treatment with oseltamivir AS SOON AS POSSIBLE from the first appearance of your flu symptoms or soon after you are exposed to the flu. If you feel worse or develop new symptoms during treatment with oseltamivir, or if your flu symptoms do not start to get better, you should contact your healthcare professional. 

• You can take oseltamivir with food or without food. There is less chance of stomach upset if you take it with a light snack, milk, or a meal.
• If you are taking oseltamivir for oral suspension, your pharmacist will give you a dosing dispenser to measure the proper amount of oral suspension for your dose. Follow your healthcare professional's instructions on how to measure the proper dose for you. Review the instructions below on how to use the dispenser and ask your pharmacist if you have any questions. If you lose or damage the dispenser and cannot use it, contact your healthcare professional or pharmacist for advice on the proper dose.
• If oseltamivir for oral suspension is not available, your healthcare provider may instruct you to open oseltamivir capsules and mix the contents with sweetened liquids such as regular or sugar-free chocolate syrup, corn syrup, caramel topping, or light brown sugar (dissolved in water). Please follow the dosing instructions below.
• If you forget to take your medicine, take the missed dose as soon as you remember, except if it is 2 hours or less before your next dose. Then continue to take oseltamivir at the usual times. Do not take 2 doses at a time to make up for a missed dose. If you miss several doses, tell your healthcare professional and follow the advice given to you.

DOSING INSTRUCTIONS FOR PATIENTS:

To Prepare a Dose of oseltamivir for oral suspension

• Shake closed bottle well for about 5 seconds before each use.
• Remove child-resistant cap.
• Before inserting the tip of the oral dispenser into bottle adapter, push the plunger completely down toward the tip of the oral dispenser. Insert tip firmly into opening of the bottle adapter.
• Turn the entire unit (bottle and oral dispenser) upside down.
• Pull the plunger out slowly until the desired amount of medication is withdrawn into the oral dispenser. The 12.5 mL (75 mg) dose is obtained by filling the dispenser twice, once to the 10 mL graduation, and a second fill to the 2.5 mL graduation.
• Turn the entire unit right side up and remove the oral dispenser slowly from the bottle.
• Dispense directly into mouth. Do not mix with any liquid prior to dispensing.
• Close bottle with child-resistant cap after each use.
• Disassemble oral dispenser, rinse under running tap water and air dry prior to next use.

If your healthcare provider directs you to mix the contents of oseltamivir capsules with sweetened liquids, follow instructions carefully to ensure proper dosing.

• Holding one capsule over a small bowl, carefully pull the capsule open and pour the complete contents of the capsule into the bowl.
• Add to the capsule contents a small amount of a sweetened liquid such as chocolate syrup (regular or sugar-free), corn syrup, caramel topping, or light brown sugar (dissolved in water) that the child will consume completely.
• Stir the mixture and give the entire dose to the child.

Take oseltamivir exactly as prescribed by your doctor. Follow the directions on your prescription label carefully. 

If you have the flu:

Take oseltamivir twice a day for 5 days, once in the morning and once in the evening. You should complete the entire treatment of 10 doses (capsules or suspension), even if you feel better.

To prevent the flu:

If someone in your home has the flu, take oseltamivir once a day for 10 days or for as long as prescribed. You can take oseltamivir for up to 6 weeks if you are exposed to the flu because of an outbreak in your community. Follow your healthcare professional's advice on how long to take oseltamivir.

Although there is a fixed dosing regimen for patients 1 year and older according to weight categories, the dosing for children younger than 1 year must be calculated for each patient based on their exact weight. These children should receive 3 milligrams per kilogram twice daily for five days. These smaller doses will require a different dispenser.

If you take too much oseltamivir, call your local Poison Control Center or seek emergency medical attention right away.

Oseltamivir capsules should be stored at room temperature, 77°F (25°C) and kept in a dry place. Keep this medication out of reach of children.

Oseltamivir for oral suspension should be stored under refrigeration for up to 17 days at 36° to 46°F (2° to 8°C). Do not freeze. Alternatively, store at room temperature for up to 10 days. Discard any unused portion when you are finished with your prescribed dosing of oseltamivir.