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What You Should Know about Flu Antiviral Drugs
By Alicia Fry, MD, MPH, Medical Officer, NCIRD, Centers for Disease Control and Prevention (CDC)
Many people believe there is no treatment for a virus and you have to let it run its course. But when it comes to influenza (often called “the flu”), antiviral drugs can be used for prevention and treatment. While CDC recommends flu vaccination as the first and most important step in preventing flu, antiviral drugs are a second line of defense against the flu.
Flu antiviral drugs are prescription medications (pills, liquid, or an inhaled powder) that can be used to treat flu infection. CDC recommends two flu antiviral drugs this flu season—oseltamivir (Tamiflu®) and zanamivir (Relenza®).
Flu antiviral drugs are different from antibiotics and are not sold over-the-counter. You can only get them if you have a prescription from a doctor. While most people with the flu have mild illness and don’t need medical care or antiviral drugs, some people will greatly benefit from the use of antiviral drugs. Clinical judgment is the most important part of deciding if antiviral drugs are needed to treat flu infection.
Antiviral treatment is most effective when started as soon as possible, ideally within the first 2 days of flu symptoms. Antivirals can make you feel better and shorten the time you are sick by 1 or 2 days. They can also prevent serious complications caused by flu infection, such as pneumonia. Tamiflu® and Relenza® are usually taken for 5 days, although hospitalized flu patients may need the medicine for longer than 5 days.
Antiviral drugs are especially beneficial for people who are very sick with flu, such as people who are in the hospital, and people with flu who have a greater chance of serious complications. Those who may have a greater chance of serious flu complications include:
- children younger than 2 years old,
- adults 65 years and older,
- pregnant women and women up to 2 weeks after giving birth,
- people with chronic medical conditions (such as asthma, heart failure, chronic lung disease, and diabetes) and people with a weak immune system (due to illnesses such as HIV), and
- people younger than 19 years of age who are receiving long-term aspirin therapy.
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