Respiratory
Short-acting bronchodilators
Reliever inhalers (e.g. salbutamol) — The "reliever" inhalers that quickly open the airways in asthma and COPD.
Education and reference only. This is a plain-language class overview — it deliberately contains no doses. Always check the current Summary of Product Characteristics (SmPC), the BNF and your local formulary before prescribing or administering any medicine.
What it is
Short-acting beta-2 agonists such as salbutamol rapidly relax the airways to relieve wheeze and breathlessness in asthma and COPD. They are the classic blue "reliever" inhaler.
How it works
They stimulate beta-2 receptors on airway smooth muscle, relaxing it within minutes to widen the airways and ease airflow. The effect is fast but short-lived, which is why they relieve rather than prevent.
In practice
In practice the reliever is for symptoms and acute attacks, while control comes from the preventer. Needing a reliever more than a couple of times a week suggests asthma is not well controlled and the preventer plan needs review. In a severe attack, repeated salbutamol via a spacer (or nebuliser) is used while seeking urgent help — and a tremor or faster heart rate is an expected effect, not a reason to withhold it.
Examples
Practical use
How to take it & use it well
- Use your reliever inhaler, such as salbutamol, when you have sudden symptoms like wheeze, cough, breathlessness or chest tightness.
- It can also be used before exercise if activity tends to trigger your symptoms.
- Using a spacer can help more of the medicine reach your lungs, especially during a flare-up.
- If you find you are using it more often than usual, it is a warning sign that your asthma is not well controlled.
- Carry it with you so it is always to hand when you need quick relief.
- Check your technique with a nurse or pharmacist and keep track of how often you are reaching for it.
Common uses
- Relief of acute asthma symptoms and attacks
- Symptom relief in COPD
- Before exercise in exercise-induced asthma
Monitoring
- Frequency of use (a control marker)
- Inhaler technique
- Heart rate and potassium with high-dose acute use
Weighing it up
Advantages & disadvantages
Advantages
- It works quickly to open the airways and relieve sudden breathlessness and wheeze.
- It is reliable for treating an asthma attack and for use before exercise.
- It delivers medicine straight to the lungs, so it acts fast with limited whole-body effects.
- It is portable, easy to use and gives reassurance that relief is on hand.
- It has a long track record as a rescue treatment.
Disadvantages
- It eases symptoms but does not treat the underlying inflammation, so it is not enough on its own for most people.
- Needing it often is a sign of poor control and a higher risk of a serious attack.
- It can cause shakiness, a fast or pounding heartbeat and feeling on edge.
- Relying on it instead of a daily preventer can let asthma get worse over time.
- Its effect is short-lived, so it does not prevent symptoms returning later.
Key safety principles
What to watch for
- Frequent need signals poor control — escalate the preventer rather than just the reliever.
- Can cause tremor, palpitations and, at high doses, low potassium.
- In a severe attack, do not delay seeking emergency help.
Key interactions
What to avoid or check alongside
- Some heart and blood-pressure medicines called beta-blockers can reduce its effect and may worsen breathing in asthma.
- Water tablets and some other asthma medicines can add to a drop in potassium when high amounts are used in a severe attack.
- Caffeine and stimulant products can add to the shaky, racing-heart feeling.
- Using it alongside frequent doses of other stimulant inhalers can increase heart-related side effects.
- It does not replace your preventer inhaler, and relying on it alone leaves inflammation untreated.
Patient & carer advice
- Carry your reliever and know it is for symptoms, not daily control
- If you are using it a lot, book a review
- Learn what to do in an attack and when to call 999
Answers
Short-acting bronchodilators: frequently asked questions
How often should I use my reliever?
Only when you have symptoms or before exercise if needed. Regularly needing it more than usual suggests your asthma is not controlled and should be reviewed.
Why do I feel shaky after using it?
Shakiness and a faster heartbeat are common and usually pass quickly. But if they are severe, or you find you are needing your reliever more than usual, get checked — needing it more often can be a sign your asthma is not well controlled.
Can the reliever replace my preventer?
No. The reliever only eases sudden symptoms, while the preventer controls the underlying inflammation. Both have different jobs.
What if my reliever is not helping during an attack?
If your symptoms do not improve, are getting worse, or you are struggling to breathe, treat it as an emergency and seek urgent medical help.
Should I carry it everywhere?
Yes. Because symptoms can come on suddenly, it is best to keep your reliever with you at all times.
Authoritative sources
Always verify against the source
This overview is for orientation. For doses, interactions, contra-indications and the full monograph, use:
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