Table of ContentsView AllTable of ContentsHow It WorksFlu ComplicationsEfficacyUseContraindicationsSide EffectsDosageStorageInteractions
Table of ContentsView All
View All
Table of Contents
How It Works
Flu Complications
Efficacy
Use
Contraindications
Side Effects
Dosage
Storage
Interactions
If you want optimal results, you should see your physician for a prescription within a few days after symptoms appear.However, Tamiflu may also prevent the flu if you are exposed and take it before getting sick.
It’s essential to know that Tamiflu doesn’t replace a flu shot. Getting a vaccine every year is the best way to prevent the flu. Even if you get a flu shot, you can still take Tamiflu to feel better if the virus takes hold.
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How Tamiflu Treats the Flu
Neuraminidase is essential for the virus to replicate (make copies of itself). As a result, blocking it prevents new flu cells from developing and stops the virus from spreading.
In addition to easing flu symptoms, Tamiflu helps shorten the length of your illness if you take it within 48 hours after your symptoms appear.You can also use Tamiflu to prevent the flu virus from taking hold.
Flu Complications Tamiflu May Prevent
While many who get the flu recover quickly, it frequently causessinusandearinfections. It can worsen existing medical conditions, such ascongestive heart failure (CHF),diabetes,asthma, and other lung conditions. In severe cases, the flu causes complications likepneumoniaand heart inflammation (myocarditis).
Spreading the flu to someone else is possible before you know you have the infection.The flu virus is highly contagious and an infected person can spread it a day or two before symptoms appear and for up to seven days after they’re gone.
The Centers for Disease Control and Prevention (CDC) estimates that flu resulted in up to 41 million illnesses, 100,000 to 710,000 hospitalizations, and as many as 51,000 deaths every year between 2010 and 2023.
How Effective Is Tamiflu?
Tamiflu was approved in 1999 and proved to be an effective treatment for flu. It has been shown to reduce the duration of symptoms in people with infection, reduce complications, and improve prevention.
Observational studies, per the CDC, suggest that antiviral drugs are not vaccine substitutes but can prevent severe flu complications like pneumonia.
How To Use Tamiflu
You should start taking Tamiflu within one to two days after your symptoms appear. However, the frequency and duration of taking Tamiflu differ depending on whether you’re using it to treat or prevent the flu.
These are general guidelines for taking Tamiflu, but your needs may differ. Your healthcare provider will advise you how to take the medicine. Take it as they prescribe rather than following these guidelines.
Treating Flu
When using Tamiflu to treat the flu in adults and children aged 2 weeks and older, take a dose twice daily (morning and evening) for five days.
Preventing Flu
Tamiflu is used as a preventive measure in people exposed to the flu, but before flu symptoms appear.When preventing the flu, take the medication once a day for at least 10 days or up to six weeks during a community flu outbreak. Adults and children 1 and older can use Tamiflu to prevent an infection.
Who Should Avoid Tamiflu?
Tamiflu should not be used if you have certain conditions. Do not take Tamiflu if you’re allergic to oseltamivir or any of the ingredients in the medication. Additionally, Tamiflu is not for use in people withend-stage renal disease (ESRD)who are not currently undergoingdialysis.
Tamiflu can worsen conditions such ashuman immunodeficiency virus (HIV), AIDS, and heart,lung, orkidney disease, and any health problem that weakens your immune system. If you have any of these conditions, your healthcare provider can let you know if Tamiflu is safe for you.
The CDC recommends treating pregnant people with the flu to avoid severe illness. Tamiflu is a medication suggested for them.
Side Effects and Safety
As with all drugs, Tamiflu may cause some side effects, which usually go away. However, at times, they can be severe and require medical care.
Common Side Effects
Call your healthcare provider if these common side effects don’t improve or worsen:
Severe Side Effects
Some side effects that follow Tamiflu usage can be severe. If you experience any of the following symptoms, call your healthcare provider immediately:
Children and teenagers with the flu may be at a greater risk for these side effects than adults.
Keep a close watch on yourself and others in your household taking Tamiflu. Call a healthcare provider immediately if you or a loved one shows unusual or worsening symptoms.
Dosage Recommendations
Tamiflu capsules are available in 30 milligrams (mg), 45 mg, and 75 mg strengths.
Tamiflu, also available via liquid suspension (a type of medication that contains solid particles suspended in a liquid), comes in the form of a 360 mg oseltamivir suspension.
Dosage for flu treatment in adolescents and adults:
Dosage for flu prevention in adolescents and adults:
The recommended dosage of Tamiflu capsules for preventing the flu in people 13 and older is 75 mg taken orally once daily.
Take one 75 mg capsule or 12.5 mL of oral suspension once daily for:
For people with renal impairment:
Your healthcare provider will recommend the safe dosage for using Tamiflu to treat or prevent the flu.
Dosage Guidelines For Children
The following table shows the dosage regimen of Tamiflu for children when used for the prevention (prophylaxis) and treatment of flu:
Storage Recommendations
For maximum effectiveness, keep Tamiflu in the same container and store the capsules at room temperature (between 68 and 77 degrees F). Keep the medicine away from areas of high heat and moisture, such as the kitchen and bathroom.
The liquid suspension form of Tamiflu should be kept at room temperature for up to 10 days or in the refrigerator for up to 17 days.
Potential Drug Interactions
Tamiflu may lower the effectiveness of the intranasal (nose spray) flu vaccine because it contains a live, weakened virus. Be sure your healthcare provider knows you take any of the following medications before they prescribe Tamiflu:
Your healthcare provider may need to change the doses of your medications or monitor carefully for adverse interactions.
Summary
Tamiflu is an effective antiviral medication that reduces illness duration and symptoms in people with the flu. The medicine is also used as a prophylactic treatment to prevent flu. Tamiflu is safe enough to be used in infants as young as two weeks and in women who are pregnant or breastfeeding.
However, Tamiflu is not a substitute for flu vaccinations. The World Health Organization (WHO) and the CDC recommend a yearly flu vaccine in children (6 months and older) and adults to reduce the chances of getting the infection.
12 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.US Food and Drug Administration.Tamiflu: consumer questions and answers.Parra-Rojas C, Nguyen VK, Hernandez-Mejia G, Hernandez-Vargas EA.Neuraminidase inhibitors in influenza treatment and prevention–is it time to call it a day?.Viruses. 2018;10(9):454. doi:10.3390/v10090454.Matrosovich MN, Matrosovich TY, Gray T, Roberts NA, Klenk HD.Neuraminidase is important for the initiation of influenza virus infection in human airway epithelium.J Virol. 2004;78(22):12665-12667. doi:10.1128/JVI.78.22.12665-12667.2004.Centers for Disease Control and Prevention.Key facts about influenza (flu).Centers For Disease Control.About estimated flu burden.DailyMed. Label:Tamiflu- oseltamivir phosphate capsule Tamiflu- oseltamivir phosphate powder, for suspension.Centers for Disease Control and Prevention.CDC research confirms benefits of flu antiviral drugs, even beyond 2 days after symptoms start.Centers for Disease Control and Prevention.Influenza antiviral medications: summary for clinicians.MedlinePlus.Oseltamivir.Centers for Disease Control and Prevention.What you should know about flu antiviral drugs.World Health Organization.Recommended composition of influenza virus vaccines for use in the 2023-2024 northern hemisphere influenza season.Centers for Disease Control and Prevention.Who needs a flu vaccine?
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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.US Food and Drug Administration.Tamiflu: consumer questions and answers.Parra-Rojas C, Nguyen VK, Hernandez-Mejia G, Hernandez-Vargas EA.Neuraminidase inhibitors in influenza treatment and prevention–is it time to call it a day?.Viruses. 2018;10(9):454. doi:10.3390/v10090454.Matrosovich MN, Matrosovich TY, Gray T, Roberts NA, Klenk HD.Neuraminidase is important for the initiation of influenza virus infection in human airway epithelium.J Virol. 2004;78(22):12665-12667. doi:10.1128/JVI.78.22.12665-12667.2004.Centers for Disease Control and Prevention.Key facts about influenza (flu).Centers For Disease Control.About estimated flu burden.DailyMed. Label:Tamiflu- oseltamivir phosphate capsule Tamiflu- oseltamivir phosphate powder, for suspension.Centers for Disease Control and Prevention.CDC research confirms benefits of flu antiviral drugs, even beyond 2 days after symptoms start.Centers for Disease Control and Prevention.Influenza antiviral medications: summary for clinicians.MedlinePlus.Oseltamivir.Centers for Disease Control and Prevention.What you should know about flu antiviral drugs.World Health Organization.Recommended composition of influenza virus vaccines for use in the 2023-2024 northern hemisphere influenza season.Centers for Disease Control and Prevention.Who needs a flu vaccine?
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
US Food and Drug Administration.Tamiflu: consumer questions and answers.Parra-Rojas C, Nguyen VK, Hernandez-Mejia G, Hernandez-Vargas EA.Neuraminidase inhibitors in influenza treatment and prevention–is it time to call it a day?.Viruses. 2018;10(9):454. doi:10.3390/v10090454.Matrosovich MN, Matrosovich TY, Gray T, Roberts NA, Klenk HD.Neuraminidase is important for the initiation of influenza virus infection in human airway epithelium.J Virol. 2004;78(22):12665-12667. doi:10.1128/JVI.78.22.12665-12667.2004.Centers for Disease Control and Prevention.Key facts about influenza (flu).Centers For Disease Control.About estimated flu burden.DailyMed. Label:Tamiflu- oseltamivir phosphate capsule Tamiflu- oseltamivir phosphate powder, for suspension.Centers for Disease Control and Prevention.CDC research confirms benefits of flu antiviral drugs, even beyond 2 days after symptoms start.Centers for Disease Control and Prevention.Influenza antiviral medications: summary for clinicians.MedlinePlus.Oseltamivir.Centers for Disease Control and Prevention.What you should know about flu antiviral drugs.World Health Organization.Recommended composition of influenza virus vaccines for use in the 2023-2024 northern hemisphere influenza season.Centers for Disease Control and Prevention.Who needs a flu vaccine?
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Centers for Disease Control and Prevention.Key facts about influenza (flu).
Centers For Disease Control.About estimated flu burden.
DailyMed. Label:Tamiflu- oseltamivir phosphate capsule Tamiflu- oseltamivir phosphate powder, for suspension.
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MedlinePlus.Oseltamivir.
Centers for Disease Control and Prevention.What you should know about flu antiviral drugs.
World Health Organization.Recommended composition of influenza virus vaccines for use in the 2023-2024 northern hemisphere influenza season.
Centers for Disease Control and Prevention.Who needs a flu vaccine?
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