Controller vs. Rescue Inhalers: Why Do People With Asthma Need Both?

The difference between controller and rescue inhalers is that a controller is taken on a schedule to reduce airway inflammation, while a rescue (quick-relief) inhaler relaxes tightened airway muscles within minutes. Some as-needed inhalers also contain an inhaled corticosteroid. Many people with asthma use both, though some plans combine them in one inhaler. This article explains how each works, how to tell them apart, what frequent rescue use can suggest, and which symptoms need emergency care.

Controller vs. rescue inhalers: the basic difference

Asthma involves two overlapping problems in the airways. The lining of the airways can become inflamed and swollen, and the muscles wrapped around the airways can tighten. MedlinePlus, from the National Institutes of Health, describes asthma as a chronic condition in which the airways can swell and narrow, causing wheezing, coughing, chest tightness and shortness of breath (MedlinePlus: Asthma).

The two kinds of inhaler target these two problems:

• Controller (maintenance) inhalers are used regularly, often every day, even when you feel fine. They aim to reduce inflammation over time so symptoms and flare-ups happen less often.
• Rescue (quick-relief) inhalers are used when symptoms start or before a known trigger such as exercise, if your clinician has advised that. They relax the tightened airway muscles and can bring relief within minutes for many people.

Think of a controller as the long-term plan and a rescue inhaler as the fire extinguisher. An extinguisher helps in the moment, but it does not fix whatever keeps starting the fires.

Why a rescue inhaler alone may not be enough

Because a rescue inhaler can relieve symptoms quickly, it is easy to feel that it is working well. Relief of tightness, however, does not necessarily mean the underlying inflammation has settled. Several factors contribute to how well asthma is controlled, including triggers, allergies, infections, and how consistently preventive medicine is used.

If you find yourself reaching for a rescue inhaler more often than before, or more often than your asthma action plan expects, it can be a sign that asthma is not well controlled. Tell your clinician, because your treatment plan may need to be reviewed. Do not change the dose or timing of any prescription on your own.

Common types of controller medicine

Your clinician chooses a controller based on your age, symptom pattern, test results and other conditions. A review in PubMed Central discusses factors clinicians weigh when choosing among inhaler types (What to consider before prescribing inhaled medications: a pragmatic approach for evaluating the current inhaler landscape). Common categories include:

• Inhaled corticosteroids. These are a widely used type of controller. They act directly in the airways to reduce inflammation. They are different from prednisone and other steroid pills or liquids, which act throughout the body. If you take oral steroids for a flare, the related article Prednisone: Uses, Side Effects, Tapering and Safety covers that medicine.
• Combination inhalers. Some products pair an inhaled corticosteroid with a long-acting bronchodilator, a medicine that relaxes airway muscles for longer than a short-acting rescue inhaler does.
• Other controller options. Depending on the case, clinicians may consider other medicines, such as leukotriene modifiers taken by mouth or biologic injections for certain types of severe asthma.

Labeling for long-acting bronchodilators used in asthma advises against using them without an inhaled corticosteroid. Read the patient information that comes with your product, and ask your prescriber or pharmacist how your specific inhaler is meant to be used.

Common types of rescue medicine

A familiar rescue medicine is albuterol, a short-acting beta agonist. Our article on Albuterol Inhalers: Uses, Side Effects, and Inhaler Technique covers its side effects and technique in detail, so this page will not repeat that. In brief, albuterol can cause a shaky feeling or a faster heartbeat in some people, and you should tell your clinician if side effects bother you.

The 2020 Focused Updates to the Asthma Management Guidelines from the NAEPP and the GINA strategy describe, for certain age groups and severities, a single inhaler containing an inhaled corticosteroid plus formoterol, a fast-acting long-acting bronchodilator, used both daily and as needed. GINA discourages treating asthma with a short-acting rescue inhaler alone. Whether an ICS-formoterol inhaler suits you depends on your age, severity and current plan, so raise it with your clinician instead of switching on your own.

How to tell which inhaler is which

Inhalers vary by brand, color and device, and color is not a reliable guide. The safest approach is to check the label and ask your pharmacist to help you identify each one.

• Read the drug name and the directions on the pharmacy label.
• Ask your clinician to write on your asthma action plan which inhaler is for daily use and which is for symptoms.
• Consider labeling each device with a marker or a sticker so you can tell them apart when you are short of breath.
• Keep the rescue inhaler where you can reach it quickly, such as in a bag or pocket.

Why technique and consistency matter

Inhaler technique and consistent use are associated with better asthma control in several studies. One study of adults in Japan, published in the National Institutes of Health's PubMed Central library, examined how adherence to inhaled corticosteroids and inhaler handling errors related to asthma control (Influence of Adherence to Inhaled Corticosteroids and Inhaler Handling Errors on Asthma Control in a Japanese Population). In that study, handling errors and lower adherence were associated with poorer asthma control, and findings in other populations may differ.

Practical steps that may help:

• Ask your pharmacist or clinician to watch you use each inhaler and point out any errors.
• Ask whether a spacer (a tube attached to some inhalers) is appropriate for you or your child.
• Link your controller to a daily habit, such as brushing your teeth, so it is easier to remember.
• Check the dose counter or the expiration date so you do not run out unexpectedly.

Some people also use remote monitoring tools or videos to support technique and adherence. A review in PubMed Central looked at remote monitoring in asthma (Remote monitoring in asthma: a systematic review), and a community pharmacy study explored web-based videos to improve inhalation technique (Use of Web-Based Videos in a Community Pharmacy to Optimize Inhalation Technique). Ask your care team whether any of these approaches fit your situation.

Side effects and cautions with controller inhalers

Inhaled corticosteroids deliver medicine mainly to the lungs, but some can stay in the mouth and throat. Possible local effects include hoarseness and a yeast infection of the mouth called thrush. Rinsing your mouth with water and spitting after each dose may help reduce this. Tell your clinician if you notice white patches in your mouth or a persistent hoarse voice.

Any medicine can cause side effects, and the right balance of benefit and risk is individual. Do not stop a prescribed controller because you feel well. Symptoms may be quiet because the medicine is working. If you are worried about side effects, ask your prescriber about options.

Medicines that can interfere with asthma treatment

Some medicines for other conditions can affect the airways or work against rescue inhalers. Non-selective beta-blockers, including some eye drops, can trigger airway narrowing and are generally avoided in people with asthma. Tell every prescriber that you have asthma so they can choose carefully. Our article What Do Beta-Blockers Do, and Why Do They Make Some People Tired? explains how this drug class works. Do not stop a heart or blood pressure medicine on your own; ask your prescriber first.

Asthma vs. COPD: why the right inhaler depends on the diagnosis

Wheezing and breathlessness are not always asthma. COPD and chronic bronchitis can cause similar symptoms and are more common in people who smoke or have long-term exposure to lung irritants. MedlinePlus has pages on COPD and chronic bronchitis. Inhaler choices can differ between conditions, so a clinician needs to assess your symptoms, history and breathing tests. For how adult asthma is diagnosed, see our separate article on adult-onset asthma.

Children and inhalers

Children with asthma may use controller and rescue medicines too, sometimes with a spacer or a nebulizer. Dosing in children depends on the specific product and the child, so follow the label and the instructions of your pediatrician or pharmacist. Do not calculate or adjust a child's dose yourself. MedlinePlus offers an overview of asthma in children. Make sure school staff and caregivers have a written asthma action plan and know where the rescue inhaler is kept.

Building an asthma action plan

An asthma action plan is a written guide you create with your clinician. It commonly describes:

• Which inhaler to use every day and which to use for symptoms.
• How to recognize that asthma is getting worse, such as more night waking, more cough or needing the rescue inhaler more often.
• What steps to take for mild worsening, as directed by your clinician.
• Which symptoms mean you should get emergency help.

Bring your inhalers to appointments so your clinician can review them and your technique.

When a rescue inhaler is not enough

A rescue inhaler is meant to bring relief. If it does not help, or relief wears off quickly, follow the red-zone steps in your asthma action plan and use the emergency list below. Severe asthma attacks can be life-threatening, so follow your action plan early rather than waiting to see whether symptoms settle. Sudden breathing trouble with swelling of the lips, tongue or throat or hives may be a severe allergic reaction and is also on that list.

When to Seek Medical Care