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Compare Relenza vs. Tamiflu

Head-to-head comparisons of medication uses, side effects, warnings, and more.

Key takeaways

Relenza (zanamivir) and Tamiflu (oseltamivir) are both antiviral medications used to treat and prevent the flu, but they have some key differences. Relenza is inhaled through a Diskhaler, making it a good option for those who have trouble swallowing pills, while Tamiflu is taken orally as a capsule or liquid. Relenza is approved for flu treatment in people 7 years and older and for prevention in those 5 years and older. In contrast, Tamiflu can be used for treatment in children as young as 2 weeks old and for prevention in those 1 year and older. Relenza is not recommended for people with asthma or COPD due to the risk of bronchospasm, whereas Tamiflu can be used by people with these conditions. Tamiflu has a generic version available, which can be more cost-effective. Both medications need to be started within 48 hours of flu symptoms to be effective.

  • Relenza (zanamivir)
    Tamiflu (oseltamivir)
  • Relenza (zanamivir)
    Tamiflu (oseltamivir)

  • Summary of Relenza vs. Tamiflu

    Summary for Antiviral
    Prescription only

    Relenza (zanamivir) is an antiviral medication. It can help ease flu symptoms and prevent the flu in certain adults and children. But it doesn't replace the seasonal flu vaccine. Relenza (zanamivir) comes as an inhaler that's inhaled by mouth twice daily for flu treatment or once daily for flu prevention. Because of the rare risk of bronchospasm, people who have asthma or chronic obstructive pulmonary disease (COPD) aren't recommended to use this medication. Common side effects include runny nose and dizziness. Relenza (zanamivir) is brand name only and not available as a generic medication.

    Summary for Antiviral
    Prescription only

    Tamiflu (oseltamivir) works well to treat the flu, but you have to take your first dose within 48 hours of the start of your flu symptoms. It can also help prevent the flu if you've recently been in close contact with someone who has the flu. Kids as young as 2 weeks old can take Tamiflu (oseltamivir), but keep in mind that the pediatric dosing is different than adult dosing. It's only available with a prescription (not available over the counter), so don't wait to see your provider if you start feeling sick. This medication comes as a brand or generic capsule or fruit-flavored liquid. Tamiflu (oseltamivir) can cause side effects like nausea and vomiting.

  • Indications of Relenza vs. Tamiflu

    Indications for
    •Flu treatment (flu types A and B) - age 7 years and older
    •Flu prevention (flu types A and B) - age 5 years and older
    Indications for
    •Flu treatment (flu types A and B) in people 2 weeks of age and older
    •Flu prevention (flu types A and B) in people 1 year of age and older

  • Pros and Cons of Relenza vs. Tamiflu

    Pros and Const for Antiviral
    Pros
    •Works for influenza types A and B
    •Inhaled; good option for people who don't like to take pills
    •Can prevent household members from spreading the flu to each other
    Cons
    •Not recommended for people with asthma or COPD because of risk of bronchospasm
    •Need to start early for it to work well (within 2 days of symptoms appearing)
    •Won't stop the spread of flu to others, if you're already sick with the flu
    Pros and Const for Antiviral
    Pros
    •Helps you feel better from the flu about 1 to 2 days sooner than if you didn't take anything
    •Can also help prevent you from getting the flu
    •Can be used in children as young as 2 weeks of age and pregnant women
    •Lower-cost generic version available
    Cons
    •Not a replacement for the annual flu shot
    •Requires a prescription from your healthcare provider
    •Only works if you take it within 2 days (48 hours) from when you first felt flu symptoms to treat (or when you were first in contact with someone who has the flu to prevent)

  • Common Side Effects of Relenza vs. Tamiflu

    Common Side Effects for
    •Diarrhea (3%)
    •Nausea (3%)
    •Sinus infection (3%)
    •Ear, nose, and throat infections (2%)
    •Dizziness (2%)
    •Bronchitis (2%)
    •Headache (2%)
    •Nose symptoms (2%)
    •Cough (2%)
    Common Side Effects for

    For flu treatment

    •Nausea (10%)
    •Vomiting (8%)

    For flu prevention

    •Headache (17%)
    •Nausea (8%)

  • Warnings of Relenza vs. Tamiflu

    Common Side Effects for
    •Bronchospasm (tightening of the airways)
    •Allergic reactions
    •Unusual thoughts or behavior
    •Proper use of Diskhaler
    Common Side Effects for
    •Serious skin reactions and allergic reactions
    •Unusual behavior and hallucinations
    •Reaction with nasal spray flu vaccine
    •Risk of bacterial infections
    •Hereditary fructose intolerance (for the liquid form)

  • Prices with our coupons for Relenza vs. Tamiflu

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