Asthma and Flu

Medically Reviewed by Dan Brennan, MD on December 07, 2022
5 min read

If you have asthma, you should do all you can to stay healthy. With asthma, any respiratory infection, including the flu, can affect your lungs, causing inflammation and airway narrowing.

About 5% to 20% of Americans get the flu each year. More than 200,000 people are hospitalized, according to the CDC. And since the 1970s, between 3,000 and 49,000 people have died from the flu each year. This is largely due to other infections and complications that can occur when you have the flu, particularly pneumonia.

People with lung problems, including those with asthma, are at higher risk of respiratory problems associated with flu. A flu vaccine is the best way to prevent the flu and subsequent respiratory problems associated with it, including a worsening of asthma symptoms.

Call your doctor if you experience flu or asthma attack symptoms, including:

  • Increased shortness of breath or wheezing
  • Coughing up increased amounts of mucus
  • Yellow- or green-colored mucus
  • Fever (temperature over 101 degrees Fahrenheit) or chills
  • Extreme tiredness  or generalized muscle aches
  • Sore throat, scratchy throat, or pain when swallowing
  • Sinus drainage, nasal congestion, headache, or tenderness along your upper cheekbones

Call 911 if you are having trouble breathing.



If you have symptoms of flu, call your doctor immediately for advice on how to prevent your asthma symptoms from worsening. Your doctor may prescribe an antiviral medicine to help reduce your flu symptoms and make changes to your asthma action plan.

Make sure you follow the instructions in your written asthma action plan to self-manage asthma and keep asthma symptoms controlled. In addition, continue to check your peak flow rate to make sure your breathing is in the safe zone.

There are steps you can take to help prevent infections that can trigger asthma symptoms:


Two types of flu vaccine exist - a shot and a nasal spray.

Flu shots don't contain a live virus and cannot cause the flu. The nasal flu vaccine, called FluMist, contains weakened flu viruses, and does not cause flu. People with asthma should receive the flu shot vaccine, not FluMist.

Other options include:

  • Intradermal shots use smaller needles that only go into the top layer of the skin instead of the muscle. They are available for those ages 18 to 64.
  • Egg-free vaccines are now available for those ages 18 to 49 who have severe egg allergies.
  • High-dose vaccines are meant for those age 65 and older and may better protect them from the flu.



Flu vaccines work the same way for everyone, including those with asthma. They cause antibodies to develop in your body. These antibodies provide protection against infection from the flu. This antibody reaction may cause fatigue and muscle aches in some people.

Each year, the flu vaccine contains several different kinds of flu viruses. The strains chosen are the ones that researchers think are most likely to show up that year. If the choice is right, the flu vaccine is about 60% effective in preventing the flu. However, the vaccine is less effective in older people and those with a weakened immune system.

The CDC recommends that everyone ages 6 months and older be vaccinated each year against the flu. There are several groups in whom the flu vaccine is particularly important. These people are either at a higher risk for complications from the flu themselves, or are around people who are at high risk for flu complications. These include:

  • Women who are pregnant
  • Children under age 5 -- especially those under age 2
  • Adults ages 50 and older
  • Adults and children with chronic health conditions, including asthma and other conditions that depress the immune system”
  • Caregivers to those at risk for flu-related complications, including health care workers and caregivers to very young children
  • Older people who live in nursing homes and other long-term care facilities


Flu season may begin as early as October and run through May. If you have asthma, the best time to get the flu vaccine is as soon as it is available, ideally by October. But getting vaccinated in January or later still can be beneficial if the flu virus is still around. It takes about two weeks for the flu vaccine to become fully effective in preventing the flu.

The American Lung Association (ALA) offers an electronic flu vaccine clinic locator. Visit its web site, enter a zip code and a date (or dates), and receive information about clinics scheduled in your area. You can also check with your pharmacist. Most retail pharmacies offer flu shots.

If you or your loved one has asthma, talk to your doctor about getting a flu vaccine.