What's the Difference Between Rescue and Controller Medications?

The two main types of asthma medicine are controller medications and rescue medications:

  1. Rescue medications, also called quick-relief or fast-acting medications, work immediately to relieve asthma symptoms when they occur. They're often inhaled directly into the lungs, where they open up the airways and relieve symptoms such as wheezing, coughing, and shortness of breath, often within minutes. But as effective as they are, rescue medications don't have a long-term effect.
  2. Controller medications, also called preventive or maintenance medications, work over a period of time to reduce airway inflammation and help prevent asthma symptoms from occurring. They may be inhaled or swallowed as a pill or liquid.

Rescue Medications

The most-prescribed rescue medications are quick-acting bronchodilators (usually given through an inhaler or a nebulizer), which loosen the tightened muscles around inflamed airways. The most common of these, beta2-agonists, are related to adrenaline and usually work within minutes to provide temporary relief of symptoms.

If a bronchodilator alone doesn't resolve a severe flare-up, other medications may be given by mouth or injection to help treat it.

If your child has been prescribed rescue medication, it's important to keep it on hand. That means at home, at the mall, at sports practice, and even on vacation.

Rescue medications, although an important part of asthma treatment, can be overused. Talk with your doctor about how often your child uses the rescue medication. If it's too often, the doctor also might prescribe a controller medicine, designed to prevent asthma flare-ups from happening.

Controller Medications

Because airways can be inflamed even in between flare-ups, controller medications might be needed to prevent unexpected asthma flare-ups. Slower-acting controller medicines can take days to weeks to start working, but when they do, they prevent airway inflammation and keep the lungs from making too much mucus.

There are a variety of controller medications, but inhaled corticosteroids are most common. They're usually given through an inhaler or nebulizer. Despite their name, corticosteroids are not the same as performance-enhancing steroids used by athletes. They're a safe and proven form of treatment for asthma.

In fact, inhaled corticosteroids are the preferred long-term treatment for kids with frequent asthma symptoms. Research shows that they improve asthma control and their risk of causing long-term negative effects is minimal. (But corticosteroids that are swallowed in liquid or pill form can cause side effects if used daily over a long period of time.)

Long-acting bronchodilators also can be used as controller medications. These relax the muscles of the airways for up to 12 hours, but can't be used for quick relief of symptoms because they don't start to work immediately.

Even if your child takes controller medicine regularly, rescue medication will still be needed to handle flare-ups when they occur.

Working With the Doctor

Your doctor will determine which type of medicine your child needs based on the frequency and severity of asthma symptoms. Be sure to report any concerns or changes in the symptoms to help your doctor select the best course of treatment. Both the type and dosage of medication needed are likely to change to continue giving your child the best quality of life and prevent flare-ups.

You're an important player in your child's asthma treatment. For example, you can track how well the medicine is working by using a peak flow meter. You also can record information in an asthma diary and ask your doctor to create an asthma action plan, if you don't already have one.

Reviewed by: Elana Pearl Ben-Joseph, MD
Date reviewed: August 2011
Originally reviewed by: Nicole Green, MD

Kids Health

Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.

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