Fast-acting bronchodilators

Fast-acting bronchodilators are reliever medications (also called rescue medications) used to relieve acute asthma symptoms (asthma attacks) and to prevent asthma symptoms caused by exercise. They act quickly, but most act only for short periods of time. When your asthma gets worse, your doctor may recommend that you increase the amount of rescue medication you're taking.

Bronchodilators work by opening up the airways, making it easier to breathe. Beta agonists (also called beta-2 agonists) are the main type of fast-acting bronchodilator available in Canada for asthma treatment.

Most fast-acting bronchodilators start working in 1 to 5 minutes, and their effects last for 4 to 6 hours. Formoterol is a bronchodilator that can be classified as both fast-acting (available in a single inhaler as Oxeze® or as part of a combination product, Symbicort®,) and long-lasting (available in a single inhaler as Foradil®). It starts working within 1 to 3 minutes, and its effects last about 12 hours. However, formoterol should only be used as a reliever medication when used in combination with a controller medication called budesonide.

Fast-acting bronchodilators available in Canada for asthma are:

Beta agonists:

  • formoterol (Oxeze®)
  • salbutamol (Ventolin® and generics)
  • terbutaline (Bricanyl®)
  • orciprenaline (generics)

Most bronchodilators are inhaled using an asthma inhaler, which is a handheld device that delivers the medication when you inhale so it goes directly into the lungs. Some are also available as liquids that can be delivered through a nebulizer (a machine that vaporizes the medications so they can be inhaled through a mask). Salbutamol is available as an inhaler, pill, injection, and oral liquid. Orciprenaline is available as an oral liquid.

Side effects of bronchodilators include:

  • for beta agonists: nervousness, shaking, fast heartbeat, and palpitations

Not everyone will experience these side effects, and other side effects not listed here may also occur. If you have questions about side effects, you should talk to your pharmacist. Contact your doctor if you notice any side effects that bother you.