A long-acting bronchodilator inhaler (LABA)
Salmeterol
A long-acting bronchodilator (LABA) for asthma and COPD; in asthma it must always be combined with an inhaled steroid and is never a rescue inhaler.
What is Salmeterol?
Salmeterol is a long-acting bronchodilator, a LABA, that opens up the airways and keeps them open for many hours. It is used regularly in asthma and COPD to ease breathing, but it is not a rescue treatment for sudden attacks.
Education and reference only. This is a plain-language guide to Salmeterol — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Salmeterol is a long-acting bronchodilator — a "LABA" (long-acting beta-agonist) — that opens up the airways and keeps them open for many hours. It is used in asthma and in chronic obstructive pulmonary disease (COPD) to ease breathlessness and reduce flare-ups. A crucial point in asthma is that salmeterol must always be used together with an inhaled steroid (preventer) and never on its own, for safety reasons; in practice it is usually given as a single combination inhaler that contains both. It is not a rescue inhaler and does not act fast enough to relieve a sudden attack. In the UK and US the active ingredient and the original brand (Serevent) are the same.
How it works
The muscle wrapped around the airways can tighten and narrow them, making breathing harder. Salmeterol stimulates beta-2 receptors on this muscle, telling it to relax, so the airways widen and stay open. Unlike a short-acting "blue" reliever, salmeterol both starts more slowly and lasts much longer, which makes it useful for steady, background control but unsuitable for the rapid rescue of a sudden attack. In asthma it eases the muscle tightening but does nothing for the underlying inflammation, which is why an inhaled steroid must always be used alongside it — using a LABA alone in asthma can mask worsening inflammation and is unsafe.
Company & origin
Originated / developed by: Glaxo.
Salmeterol was discovered by Glaxo in the UK in the 1980s as a long-acting modification of salbutamol; it was first marketed in the UK as Serevent in 1990 and approved by the US FDA in 1994.
What it treats
Conditions Salmeterol is used for
Practical use
How to take Salmeterol
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Use salmeterol regularly as a preventer of symptoms, not as a reliever; it does not work fast enough for a sudden asthma attack.
- In asthma, it must always be used together with an inhaled steroid, never on its own, as using a LABA alone in asthma can be dangerous.
- Keep using your separate fast-acting reliever inhaler for sudden breathlessness.
- Learn the correct inhaler technique from your nurse or pharmacist so the medicine reaches your airways.
- Seek urgent help if your breathing worsens or your reliever is needed much more than usual.
Weighing it up
Advantages & disadvantages of Salmeterol
Advantages
- Provides long-lasting opening of the airways, helping control symptoms through the day and night.
- Useful add-on in asthma and COPD when an inhaled steroid alone is not enough.
- Often combined with an inhaled steroid in a single inhaler for convenience.
- Can reduce breathlessness and improve day-to-day activity.
Disadvantages
- Not a rescue treatment, so it must not be relied on for sudden attacks.
- In asthma it must never be used without an inhaled steroid, as a LABA alone is unsafe.
- Can cause tremor, headache, palpitations or muscle cramps.
- Needs good inhaler technique to be effective.
Practical use
Good to know
It is taken regularly to keep the airways open, not when you feel breathless in the moment — a fast-acting reliever is still needed for sudden symptoms. In asthma it should never be used without an inhaled steroid, which is why it is almost always prescribed as a combination inhaler. Good inhaler technique matters a great deal, and rinsing the mouth is sensible if the inhaler also contains a steroid. Mild tremor (shaky hands), a faster heartbeat or palpitations can occur, especially at first, and usually settle. If you are needing your rescue inhaler more, or symptoms are worsening despite regular use, this needs prompt review rather than simply using more.
Who should not take it / use with caution
- In asthma it must never be used as the only treatment — it is always combined with an inhaled steroid; using a LABA alone in asthma is unsafe.
- Used with caution in significant heart disease, irregular heart rhythms, an overactive thyroid, and in diabetes (it can affect blood sugar and potassium).
- Care in pregnancy and breastfeeding, where keeping asthma well controlled is itself important and treatment is individualised.
Monitoring
- Asthma or COPD control and flare-up frequency
- How often the rescue inhaler is needed
- Inhaler technique; pulse and (where relevant) blood potassium
Side effects
- Tremor (shaky hands), a faster heartbeat or palpitations, and headache, especially when starting; these usually ease.
- Muscle cramps and, if it contains a steroid, a hoarse voice or oral thrush (reduced by rinsing the mouth).
- Rarely, a drop in blood potassium, or paradoxical tightening of the airways straight after using the inhaler — if breathing suddenly worsens after a dose, use a rescue inhaler and seek advice.
Key interactions
- Its effects on heart rate and tremor can be increased by other stimulant-type medicines and by high caffeine intake.
- Some medicines lower blood potassium (certain water tablets, steroids and other airway medicines), and the effect can add up.
- Beta-blockers (including some eye drops for glaucoma) can oppose its action and may worsen asthma, so they are used carefully or avoided.
Available as: Inhalers — including a dry-powder device and a metered-dose inhaler — and very commonly a combination inhaler that also contains an inhaled steroid.
Answers
Salmeterol: frequently asked questions
Can I use salmeterol to relieve a sudden asthma attack?
No. Salmeterol is long-acting and starts too slowly to rescue a sudden attack — you still need your fast-acting reliever (usually the "blue" inhaler) for that. Salmeterol is for steady, background control, used regularly rather than in the moment.
Why must salmeterol be taken with a steroid inhaler in asthma?
In asthma, salmeterol opens the airways but does nothing for the underlying inflammation. Used alone it can mask worsening asthma and has been linked to safety problems, so it must always be combined with an inhaled steroid — which is why it is usually given as a single combination inhaler containing both.
It makes my hands shake and my heart race — is that dangerous?
Mild tremor (shaky hands), a faster heartbeat or palpitations are common when starting a long-acting bronchodilator and usually settle. If they are severe, persistent or come with chest pain or a very irregular heartbeat, get them checked. Cutting down on caffeine can help with the tremor.
Why am I still using my blue inhaler a lot?
Needing your fast-acting reliever often, or finding salmeterol is not controlling symptoms, is a sign your asthma or COPD may not be well controlled — not a reason to simply use more salmeterol. Book a review, as your treatment or technique may need adjusting.
What is the difference between salmeterol and Serevent?
They are the same medicine — salmeterol is the generic (active-ingredient) name and Serevent is the original brand name, used in both the UK and US. Salmeterol is also found inside several combination inhalers under other brand names, paired with an inhaled steroid.
The wider class
About Long-acting bronchodilators
Salmeterol belongs to the long-acting bronchodilators class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF: Salmeterol.
- electronic Medicines Compendium (SmPC): Salmeterol (Serevent).
- NICE CKS: Salmeterol inhaler.
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