Please note: This information was current at the time of publication but now may be out of date. This handout provides a general overview and may not apply to everyone. 

brand logo

Am Fam Physician. 1998;58(1):109-113

See related article on asthma.

To keep your asthma under control, you need to know what to do when you have a flare-up of symptoms (sometimes this is called an “exacerbation”). First, you need to know the symptoms that tell you your asthma is getting worse (flaring up). Second, you need to know how to treat your asthma when it gets worse. Early treatment of flare-ups works the best and will help get your asthma under control quickly.

What causes asthma symptoms to flare up?

Your asthma can flare up for different reasons. If you're allergic to dust mites, pollens or molds, they can make your asthma symptoms get worse. Cold air, exercise, fumes from chemicals or perfume, tobacco or wood smoke, and weather changes can also make asthma symptoms worse. So can common colds and sinus infections. Gastroesophageal reflux (when stomach acid comes up into the back of the throat) can also cause flare-ups. You can help yourself by paying attention to the way these things affect your asthma. Your doctor might test you to find out if you're allergic to something. Then your doctor can help you avoid the things that bother your asthma.

What are the symptoms of an asthma flare-up?

Common symptoms are coughing, shortness of breath (feeling breathless), a feeling of tightness in the chest and wheezing. (Wheezing is breathing that makes a hoarse, whistling sound.) It's important to watch yourself every day for symptoms of asthma. You may have only one or two of these symptoms.

Another clue that your asthma is flaring up is that you have to take extra doses of your quick-relief asthma medicine (with an inhaler) more than twice a week because of these symptoms.

How do I know if a flare-up is serious?

Here's a good way to see how bad a flare-up is: measure your peak expiratory flow (also called “PEF”) using a peak flow meter. Your doctor can show you how to use a peak flow meter to keep track of your asthma. A peak flow meter costs less than $30, and you only have to buy it one time. First, you find out your “personal best” peak flow. This is the highest reading you can get on the meter over a two-week period when your asthma is under good control.

Here are some general guidelines you can use to find out how serious an asthma flare-up is:

  • During mild flare-ups, you may notice shortness of breath when you walk or exercise, but when you sit still, you feel okay. You can usually breathe well enough to talk in complete sentences. You may hear some wheezing, mostly at the end of exhaling (breathing out). Your peak flow readings will be 80 to 100 percent of your personal best.

  • During moderate flare-ups, you may feel short of breath when you talk or lie down, but if you sit quietly, you feel better. You may talk in a few words rather than using whole sentences because you're short of breath. You may feel anxious or tense. You may be using your neck muscles to help you take deeper breaths. You may hear loud wheezing, especially when you breathe out. Your peak flow readings will be about 50 percent to less than 80 percent of your personal best.

  • During serious flare-ups, breathing will be very difficult and faster than usual. Even when you're sitting still, you'll feel short of breath. You might be able to talk only in a few words at a time because you're so short of breath. You'll feel anxious or tense. Your peak flow readings will be less than 50 percent of your personal best. If you feel sleepy and confused, and breathing is making you more and more tired, you may be having a life-threatening problem. Serious flare-ups mean you need to be treated right away, preferably in a hospital emergency room. Don't wait to get medical help if you have the symptoms of a serious flare-up!

How is an asthma flare-up treated?

The best thing to do first if your asthma symptoms are getting worse is to use your rescue or quick-relief medicine. Ask your doctor if you're not sure what to use for quick-relief medicine. The usual inhaler dose is two to four puffs every 20 minutes for a total of three doses, or one nebulizer treatment if you have a home nebulizer.

You should be able to tell how serious the flare-up is after you use your quick-relief medicine. If you have a peak flow meter, check your PEF again after you use the quick-relief medicine. If your PEF is still very low, your flare-up is serious.

Your doctor may have given you a written “Asthma Action Plan” with directions for treating mild, moderate and severe flare-ups. (A sample “Asthma Action Plan” appears at the end of this handout.) If you don't have an action plan, ask your doctor for written directions about treating asthma flare-ups. If you have the symptoms of a serious flare-up or if your PEF is less than 50 percent of your personal best, call your doctor right away or go directly to the nearest hospital emergency room (by ambulance, if necessary).

Asthma Action Plan

Name ______________________________ Date __________________

To manage your asthma, you need to keep track of your symptoms, your medicine use and your peak expiratory flow (PEF). Using your PEF as a guide, here are some tips for treating your asthma symptoms:

  • Green means Go—you're feeling OK. Just keep using your preventive (anti-inflammatory) medicine.

  • Yellow means Be Careful—you're having some symptoms. It's time to use your quick-relief (short-acting bronchodilator) medicine, in addition to the preventive medicine.

  • Red means STOP—Your symptoms are serious. You need to get help from a doctor!

  • Your green zone is _________, which is 80 to 100 percent of your personal best peak flow. Go! Breathing is good, with no cough, wheezing or chest tightness.


  • Keep taking your usual daily medicines.

Your yellow zone is __________, which is 50 to 80 percent of your best peak flow. Be careful! You may have symptoms like coughing, wheezing or chest tightness. Your peak flow level has dropped, or you notice that you need to use quick-relief medicine more often, or you have more asthma symptoms in the morning, or asthma symptoms are waking you up at night.


  • Take ______ puffs of _________________________ (your quick-relief medicine). Repeat this dose every 20 minutes, up to ____ more times. Use ____ puffs regularly every four to six hours for the next two days.

  • Take ______ puffs of ___________________ (your anti-inflammatory medicine) ______ times per day.

  • Start taking oral steroid medicines (or increase your dose): ________________ in a dose of ____ mg every a.m. ____ p.m. _____.

  • Call your doctor or a hospital emergency room for advice today.

Your red zone is ___________, which is 50 percent or less of your best peak flow. Danger! Your peak flow number is very low, or you continue to feel worse after taking more medicines according to the directions for the yellow zone.


  • Take ______ puffs of your quick-relief medicine. Repeat this dose every 20 minutes, up to ____ more times.

  • Start taking an oral steroid medicine (or increase the dose). Take _______ mg right now.

  • Call your doctor now! If you can't reach your doctor, go to a hospital emergency room.

Call your doctor at any time if you have any of the following problems:

  • Your asthma symptoms get worse even though you're taking oral steroids


  • Inhaled quick-relief medicine isn't helping you for as long as four hours


  • Your PEF stays at 50 percent of your personal best (or gets even lower) even though you're using your action plan.

Important telephone numbers:

  • Doctor's office _____________________________

  • Doctor after hours _________________________

  • Hospital emergency room __________________

Where can I find out more about asthma?

You can find out more about asthma by telephoning or writing to the following groups:

  • American Lung Association

    Telephone (to find the local office nearest you):

    1-800-LUNG-USA (1-800-586-4872), or check your local telephone directory

    Internet address:

  • American Academy of Allergy, Asthma, and Immunology

    611 East Wells St.

    Milwaukee, WI 53202

    Telephone: 1-800-822-ASTHMA (1-800-822-2762)

    Internet address:

  • Allergy and Asthma Network/Mothers of Asthmatics, Inc.

    3554 Chain Bridge Road, Suite 200

    Fairfax, VA 22030-2709

    Telephone: 1-800-878-4403

    Internet address:

  • National Asthma Education and Prevention Program,

    National Heart, Lung, and Blood Institute Information Center

    P.O. Box 30105

    Bethesda, MD 20854-0105

    Telephone: 1-301-251-1222

    Internet address:

Continue Reading

More in AFP

Copyright © 1998 by the American Academy of Family Physicians.

This content is owned by the AAFP. A person viewing it online may make one printout of the material and may use that printout only for his or her personal, non-commercial reference. This material may not otherwise be downloaded, copied, printed, stored, transmitted or reproduced in any medium, whether now known or later invented, except as authorized in writing by the AAFP.  See permissions for copyright questions and/or permission requests.