Asthma Inhalers Explained: Controllers, Relievers, and Combination Therapy

You have two or three inhalers, and you are not sure which one to use when. Maybe you only reach for the blue one when you feel tight, and the other one sits in a drawer. That is very common, and it matters. Asthma care has changed a lot in recent years. This guide explains the different types of inhalers and what current guidelines recommend.

What asthma is

Asthma is a long-term condition where the airways in the lungs become inflamed and narrow [5]. This causes:

• Wheezing
• Shortness of breath
• Chest tightness
• Coughing, often at night or early morning

Symptoms can flare with colds, allergens, exercise, cold air, smoke, and some medications. The inflammation is often present even when you feel fine.

The types of inhalers

Relievers

Relievers (rescue inhalers) open the airways quickly. The most common is a short-acting beta agonist (SABA), called salbutamol in Canada and albuterol in the US. It works within minutes and lasts about 4 to 6 hours. It does not treat the underlying inflammation.

Controllers

Controllers (maintenance inhalers) treat the inflammation over time. The main type is an inhaled corticosteroid (ICS), such as budesonide, fluticasone, beclomethasone, ciclesonide, or mometasone. Controllers lower the risk of asthma attacks, but you may not feel them working right away.

Combination inhalers

Many inhalers combine an ICS with a long-acting beta agonist (LABA), which keeps the airways open for about 12 hours or more. Examples include budesonide-formoterol, fluticasone-salmeterol, and fluticasone-vilanterol. Formoterol is special because it starts working within minutes, so ICS-formoterol inhalers can be used as relievers too.

A LABA should never be used alone for asthma without an ICS.

What your doctor looks at

The big shift: no more reliever-only treatment

For decades, people with mild asthma were often given only a SABA reliever. Research showed that relying on SABA alone raises the risk of severe attacks. Since 2019, the Global Initiative for Asthma (GINA) no longer recommends SABA-only treatment for adults and teens [1]. Every person with asthma should get an inhaled steroid in some form [1].

GINA's preferred approach

GINA's preferred track for adults and teens uses low-dose ICS-formoterol as the reliever [1]:

• For mild asthma: ICS-formoterol taken only as needed for symptoms
• For more frequent symptoms: ICS-formoterol taken every day and also as needed, called maintenance and reliever therapy (MART)

An alternative track uses a daily ICS controller with a separate SABA reliever, or ICS taken whenever SABA is used [1].

Canadian guidance

The Canadian Thoracic Society 2021 guideline also moved away from SABA-only treatment [3]. For mild asthma, it supports either as-needed budesonide-formoterol or a daily low-dose ICS with a reliever [3]. In Canada, budesonide-formoterol is approved for as-needed use in mild asthma.

US guidance

The US NHLBI 2020 focused update recommends ICS-formoterol as daily and as-needed therapy (also called SMART) as the preferred option for people 12 and older with moderate to severe persistent asthma [2]. For mild persistent asthma, it allows either daily low-dose ICS or using an ICS and SABA together as needed [2]. In the US, the FDA label for budesonide-formoterol does not include reliever use, so this guideline use is off-label. An albuterol-budesonide inhaler was approved by the FDA in 2023 for as-needed use in adults.

Signs of poor control

Clinicians check how well your asthma is controlled. Warning signs include [2] [5]:

• Using a reliever more than 2 days a week (with a SABA-based plan)
• Waking at night with asthma symptoms
• Asthma limiting your activities
• Needing steroid pills for a flare in the past year
• An emergency visit for asthma

Other checks

• Inhaler technique and use of a spacer
• Whether you take your controller as prescribed
• Triggers at home and at work
• Other conditions, such as allergies, reflux, and smoking
• Lung function tests, such as spirometry

Add-on medications

• Montelukast: a pill that blocks part of the allergy pathway. In 2020, the FDA added a boxed warning about serious mental health side effects, such as agitation, sleep problems, depression, and suicidal thoughts [4].
• Long-acting muscarinic antagonists, such as tiotropium, for some people
• Biologic injections for severe asthma, such as those targeting IgE, IL-5, IL-4/IL-13, or TSLP, usually prescribed by a specialist

Using inhalers well

• Ask your pharmacist or clinician to watch you use your inhaler.
• Use a spacer with metered-dose inhalers if advised.
• Rinse your mouth and spit after using an inhaled steroid.
• Keep your reliever with you at all times.
• Have a written asthma action plan.

Questions to ask your clinician

• Which of my inhalers is the controller and which is the reliever?
• Should I be on an ICS-formoterol plan?
• How many puffs can I take in a day before I should get help?
• Is my inhaler technique correct?
• How well controlled is my asthma right now?
• Do I need a spirometry test?
• What is in my asthma action plan?

When to get care quickly

Call 911 or go to the emergency department if:

• Your reliever is not helping, or you need it again within a few hours
• You are too short of breath to speak in full sentences
• Your lips or fingernails look blue or grey
• You feel drowsy or confused
• The skin between your ribs or at your neck pulls in with each breath

Bottom line

Relievers treat symptoms in the moment, while controllers treat the inflammation that causes attacks. Current guidelines in Canada and internationally recommend that everyone with asthma get an inhaled steroid, and many people now use one ICS-formoterol inhaler as both controller and reliever. If you use a reliever often, your asthma may not be well controlled. Ask your clinician to review your plan.

Primary AI can show you the guideline and study sources behind this topic in plain language, so you can bring better questions to your appointment.