Antiviral Drugs

Questions & Answers: Antiviral Drugs, 2009-2010 Flu Season

Who should use an antiviral medication?

Antiviral medicines are recommended for the following, at onset of flu symptoms

CDC recommends:	Antivirals, if ill with flu-like symptoms (Tamiflu/Relenza)
Age
Infants less than 2 years of age	X¹
Children aged 2 through 4 years of age	consider
Children age 5 through 18
Young adults age 19 through 24 years of age
Adults age 25 through 49 years of age
People aged 50 through 64 years of age
People aged 65 years of age and older	X
Medical Conditions
Pregnant women	X
Persons aged 5 to 64 years old who have health conditions associated with higher risk of medical complications from influenza*	X
Persons under age 19 on chronic aspirin therapy	X
Anyone hospitalized with confirmed/suspected flu	X
Living arrangements
People who live in nursing homes and other long-term care facilities	X

¹ Tamiflu is allowed for children less than 1 year under FDA emergency use authorization during current pandemic outbreak.

* Health conditions associated with higher risk include chronic disorders such as diabetes or heart, kidney or lung disease, or a weakened immune system, such as from medications or HIV infection.

For information about H1N1, www.flu.gov and www.cdc.gov/H1N1 flu have a vast array of resources.

Colorado Home Healthcare Guide: Providing Care at Home During Pandemic Flu (English and Spanish)

General Information on antiviral drugs

For more detailed information, go to: http://www.cdc.gov/h1n1flu/antiviral.htm

What are influenza antiviral drugs?

Influenza antiviral drugs are prescription drugs (pills, liquid, or inhaler) that decrease the ability of flu viruses to reproduce. While getting a flu vaccine each year is the first and most important step in protecting against flu, antiviral drugs are a second line of defense in the prevention and treatment of flu.

What is the difference between antiviral medicines for flu and antibiotics?

Antiviral medicines for flu reduce the ability of the flu viruses to make more flu viruses in the body. Antibiotics kill bacteria or slow their growth. Viruses and bacteria are very different biologically. Medicine that treats bacterial infections has no effect of viruses; medicine that treats viral infections has no effect on bacteria.

Who should take an antiviral drug?

Most healthy people who get the flu will not need to use antiviral medicines. However, antiviral drugs may be especially important for people who are very sick (hospitalized) or for people who develop flu symptoms and are at increased risk of serious complications, such as pregnant women, young children and those with chronic health conditions.

People who have a greater chance of serious flu complications can include:

Children younger than 2 years old*
Adults 65 years and older
Pregnant women and women up to 2 weeks from end of pregnancy
People with certain chronic medical conditions (such as asthma, heart failure, chronic lung disease) and people with a weak immune system (such as diabetes, HIV)
People younger than 19 years of age who are receiving long-term aspirin therapy

*It is also important to know that children who are 2 years though 4 years of age also have a higher rate of complications compared to older children, although the risk for these children is lower than the risk for children younger than 2 years.

What side effects can occur with influenza antiviral drugs?

Side effects differ for each drug. If an antiviral drug has been prescribed for you, ask your doctor to explain how to use the drug and any possible side effects. Health care professionals prescribing flu antiviral drugs should alert patients about adverse events that can occur. For more information about side effects, see Antiviral Drugs: Summary of Side Effects.

Antiviral Drugs and Children

Can children take antiviral drugs?

Yes. The two drugs recommended for use against influenza (including 2009 H1N1) this season can be used in children.

Oseltamivir (Tamiflu®) is approved by the Food and Drug Administration (FDA) for use in children 1 year of age or older. In addition, in July 2009, the FDA issued an Emergency Use Authorization (EUA) for the use of Tamiflu® in pediatric patients younger than 1 year of age.

Zanamivir (Relenza®), is approved for treatment in children 7 years and older, but should not be used by anyone with underlying lung disease, such as asthma, or severe allergy to milk proteins.

What form of antiviral drugs are available for children?

Oseltamivir (Tamiflu®) comes in an oral suspension (liquid) for children. It also comes in capsules at children's dosages. Zanamivir (Relenza®) is an inhaled powder that comes with a disk inhaler.

What are the recommendations for the use of antiviral drugs in young children?

Treatment with influenza antiviral drugs could be particularly important for children at high risk of flu-related complications, including children younger than 2 years old and children of any age with chronic health conditions like asthma, diabetes, or heart or lung disease. Providers will use clinical judgment to guide treatment decisions for healthy children.

Children ages 2 years to 4 years old without high risk conditions and who are not severely ill do not necessarily need antiviral treatment. While children 2 years to 4 years old are more likely to require hospitalizations or urgent medical care for influenza compared with older children, this risk is much lower than the risk for children younger than 2 years old.

This season, antiviral drugs are being prioritized for hospitalized patients (including children) and high risk patients who are sick with the flu.

What do other experts say about antiviral drugs and children?

The American Academy of Pediatrics (AAP) recommends antiviral drugs to treat influenza in children who are at higher risk of serious flu-related complications and who have moderate-to-severe influenza. These children in particular may benefit from a decrease in the duration of their symptoms. For more information on the AAP recommendations, visit http://www.pediatrics.org/cgi/content/full/119/4/852.

Antiviral Drugs And Pregnant Women

Information on H1N1 and pregnancy: http://www.cdc.gov/h1n1flu/pregnancy/

If I'm pregnant, what should I do if I think I have the flu?

If a pregnant woman thinks she has flu, she should call her doctor right away. If needed, he or she will prescribe an antiviral medicine that treats the flu. The medicine is most helpful if it is started soon (within the first 48 hours) after the pregnant woman becomes sick.

What should I do if I have a fever?

Fever should be treated right away. It can cause problems for the pregnant woman and her unborn child. Acetaminophen (Tylenol®) is best for a pregnant woman to use to lower a fever.

What antiviral medicines are available for pregnant women who have the flu?

Oseltamivir (Tamiflu®) or zanamivir (Relenza®) can be used to treat 2009 H1N1 flu. To get these medicines, a doctor needs to write a prescription. These medicines fight against the flu by keeping flu viruses from making more viruses in your body. If you get sick, antiviral drugs can make your illness milder and make you feel better faster. They may also prevent serious health problems that can result from flu illness. At this time, Tamiflu® is the best medicine to treat pregnant women who have 2009 H1N1 flu.

Is it safe for me to take an antiviral medicine for flu while I am pregnant?

The flu can cause severe illness and even death in pregnant women. Taking antiviral medicine can help prevent these severe outcomes. At this time, there are no studies suggesting harm to a pregnant woman or her unborn baby if she takes antiviral medicine. Studies in pregnant animals also have not raised concern for problems from taking these medicines.

Even if there was a very small chance that antiviral medicines might cause harm, having the flu could cause more harm. Being pregnant should not stop women from using antiviral medicines if their doctor advises them to take the medicine. Antiviral medicines can be taken at any stage during pregnancy.

Antiviral Drugs and Flu Vaccine

Can antiviral drugs be helpful for people unable to take the flu vaccine?

Yes. CDC and ACIP recommend use of antiviral drugs for people allergic to eggs (which can cause them to have an allergic reaction to the vaccine) or for people who previously have encountered complications from Guillain-Barre syndrome (GBS) associated with influenza vaccination. In addition, taking antiviral drugs may be recommended among persons that may not have a good immune response to the flu vaccine.

Should people use antiviral drugs before or after receiving the live attenuated influenza vaccine (LAIV) called FluMist®?

LAIV is one of two types of flu vaccine. It is given as a nasal spray and contains weakened, live virus. Flu antiviral drugs taken from 48 hours before through 2 weeks after getting LAIV can lower or prevent the vaccinated person from responding to the vaccine and the person may not get immune protection from the vaccine. Antiviral drugs can be taken with the inactivated (i.e. killed) flu vaccine.