Asthma — what it is, and how we treat it today

About this guide

Asthma is one of the most common long-term conditions we see in primary care. Around 5% of adults in Singapore have it, about 1 in 3 have had a flare-up requiring unscheduled treatment in the past year, and roughly half have missed work or school because of it. Singapore’s asthma hospital admission rates are higher than the average across OECD countries — not because the condition is harder to treat here, but largely because treatment is often underused or out of date.

The most important point we want you to take away from this guide:

Asthma is a long-term inflammatory condition. Treatment that only reacts to symptoms — the classic “puff the blue inhaler when breathless” approach — is not enough for most patients, and can make things worse over time. What modern evidence strongly supports is anti-inflammatory treatment for every patient with asthma, not just those with daily symptoms.

If you or a family member were diagnosed more than a few years ago and the treatment plan hasn’t been reviewed in a while, the plan may genuinely need updating. That’s one of the things we do at every follow-up visit.

What is asthma?

Asthma is a condition where the airways in the lungs — the small tubes that carry air in and out — become inflamed and over-sensitive. When triggered (by an infection, allergen, exercise, cold air, irritant, or sometimes stress), the airways tighten up and swell, and mucus production increases. Air becomes harder to push out — which is why the classic symptoms are wheezing, shortness of breath, chest tightness, and cough, often worse at night or early morning.

Two things are going on at once:

1. Chronic inflammation in the airway walls, present most of the time even when you feel fine. This is what needs long-term treatment to settle.
2. Episodic tightening (bronchoconstriction) of the airway muscles, which causes the acute symptoms. This is what quick-acting inhalers were originally designed to address.

Critically, the level of underlying inflammation does not always match how you feel day-to-day. A patient with few symptoms can still have enough background inflammation to put them at risk of a bad flare-up. That’s why symptom control alone is not a reliable guide to whether treatment is adequate.

How we diagnose it

Asthma is usually a clinical diagnosis — based on your history (symptom pattern, triggers, response to a trial of inhaler, family history, atopy) and a physical examination. We often confirm it objectively with:

• Spirometry — a breathing test measuring how much air you can blow out in the first second (FEV₁) and in total (FVC). A pattern of obstruction that improves after a reliever is typical for asthma.
• Peak expiratory flow (PEF) — a simple home blow-meter; patterns over a few weeks can support diagnosis and guide day-to-day monitoring.
• Blood eosinophil count — a simple finger-prick or venous blood test. A count of ≥300 cells/μL (or ≥3%) points toward the eosinophilic phenotype, which is the commonest type of asthma seen in primary care and predicts a good response to inhaled corticosteroid treatment. It supports the diagnosis when the clinical picture is borderline, and also helps us decide how aggressively to start treatment.
• Response to a trial of treatment — occasionally, a clear improvement after starting an inhaled corticosteroid is the diagnostic signal.
• In uncertain cases we may refer for more detailed lung function testing (bronchial challenge, fractional exhaled nitric oxide — FeNO) through a respiratory specialist.

Several conditions can mimic asthma, particularly in older adults — chronic obstructive pulmonary disease (COPD), post-viral cough, chronic rhinosinusitis with post-nasal drip, gastro-oesophageal reflux, and heart failure. Getting the diagnosis right matters because the treatments differ.

The big shift — why we don’t treat asthma with a blue inhaler alone anymore

For decades, the default approach to mild asthma was to hand patients a short-acting beta-agonist (SABA) — typically salbutamol (Ventolin) — and tell them to use it when breathless. Inhaled corticosteroid (“preventer”) was reserved for patients with more frequent symptoms.

Over the last decade, strong evidence has shifted this approach. We now know that:

• SABA-only treatment does not address the underlying airway inflammation. You feel better briefly but the inflammation — and the risk of a bad flare-up — remains.
• High SABA use is a marker of poor control, and is independently associated with more exacerbations, more emergency visits, and more deaths.
• Locally, about one in three patients with a severe asthma exacerbation requiring ICU admission were not on any preventer before the flare-up. These are largely preventable admissions.
• When patients are switched from SABA-only to an inhaled corticosteroid (ICS)-containing regimen, the risk of severe exacerbations falls by roughly 60%.

The current international guideline (GINA 2026) now recommends that all adolescents and adults with asthma should be on an ICS-containing inhaler, even for mild or infrequent symptoms. Short-acting beta-agonists alone are no longer recommended for long-term asthma management.

In simple terms: asthma treatment has become anti-inflammatory first, symptom-relief second. If you were last prescribed “just a blue inhaler,” it’s time for a fresh conversation.

Preventers and relievers — and how modern inhalers combine both

A little background on the two main classes of inhaler:

Preventers (controllers)

These treat the underlying inflammation. The mainstay is inhaled corticosteroid (ICS) — a very low systemic dose (much smaller than oral steroids), delivered directly into the airway. Examples of ICS used in Singapore:

• Budesonide (Pulmicort)
• Fluticasone (Flixotide)
• Beclomethasone (Beclo-Asma)

ICS takes days to weeks of consistent use to reach full effect. You don’t feel it working the way you feel a reliever — but the reduction in flare-ups is real and large.

Relievers

These quickly open up airways by relaxing the muscle layer. The classic “just-a-reliever” class is short-acting beta-agonist (SABA) — almost always salbutamol (Ventolin) in Singapore. Effect in minutes, lasting 3–6 hours.

The modern combination — ICS-formoterol

The most important development in asthma treatment has been the recognition that formoterol, a long-acting beta-agonist (LABA), has a fast onset of action — unlike older LABAs such as salmeterol (which is long-acting but slow to start). This makes ICS-formoterol combinations suitable for use both as regular preventer and as reliever — all in one inhaler. This approach is called AIR (Anti-Inflammatory Reliever) or, when used for both daily maintenance and as-needed relief, MART (Maintenance And Reliever Therapy).

The most commonly-used ICS-formoterol products in Singapore are:

• Budesonide-formoterol (Symbicort) — locally registered for patients aged 12 and older
• Beclomethasone-formoterol (Fostair) — locally registered for patients aged 18 and older

Why this matters in practice: every time you reach for a reliever puff, you also get a small dose of anti-inflammatory treatment. You can’t accidentally “over-rely on the reliever” in the way you could with salbutamol. Studies consistently show fewer exacerbations and fewer hospital visits compared to the older SABA-reliever approach, especially in people who are inconsistent with daily preventer use.

How we choose and step up treatment

Current guidance — both the ACE Clinical Guideline and GINA — supports a stepwise approach based on symptoms, exacerbation risk, and what you’re already on. A simplified version for adolescents and adults:

Key points:

• ICS-containing treatment is recommended at every step. There is no “Step 1 = SABA only” anymore.
• Stepping up is warranted if you still have frequent symptoms, night waking, exercise limitation, or frequent reliever use despite current treatment.
• Stepping down is reasonable after symptoms have been well controlled for at least 3 to 6 months — but we usually hold off stepping down during higher-risk periods (pregnancy, upcoming travel, known allergy season, period of high stress).
• Stopping ICS altogether is not recommended in patients aged 6 years and older with asthma — it increases the risk of future exacerbations.

Children aged 6–11 and younger children are managed on slightly different algorithms — we’ll cover children briefly further down.

Inhaler technique — probably the single biggest thing you can improve

Up to 70–90% of patients do not use their inhalers correctly. The right inhaler used poorly can deliver less than half the prescribed dose. No medication change will make up for this.

A few universal pointers (specific techniques vary by device):

• Breathe out first, gently, to empty your lungs.
• Seal your lips tightly around the mouthpiece — no gaps.
• For pressurised metered-dose inhalers (pMDIs / “puffers”): release the medication as you start to breathe in slowly and deeply, then hold your breath for about 10 seconds if you can.
• For dry powder inhalers (DPIs) like Turbohaler or Accuhaler: breathe in fast and deep (faster than with a pMDI).
• Wait about 30 seconds between puffs if multiple puffs are prescribed.
• Rinse your mouth and gargle after any ICS-containing inhaler to reduce the risk of oral thrush and hoarseness.
• Use a spacer (e.g. Aerochamber) with your pMDI — it improves drug delivery dramatically and is essential for children and for anyone struggling with coordination.

At every follow-up visit, we’ll watch you use your inhaler and correct anything drifting. Please don’t take offence — even long-standing patients often pick up small errors over the years.

Your asthma action plan

Every patient with asthma should have a written asthma action plan (WAAP) — a simple one-page document that tells you what to do at three levels:

1. Green zone (well-controlled) — your usual daily treatment. Symptoms infrequent, no night waking, no activity limitation. If you use a peak flow meter at home, this is typically ≥80% of your personal best.
2. Yellow zone (worsening symptoms) — what to step up, when, and for how long (typically an increase in ICS or ICS-formoterol use). Peak flow 50–79% of your best, or any worsening symptoms (increased reliever use, some night waking, activity limitation).
3. Red zone (danger) — what to do (often a short course of oral prednisolone) and when to come in or call 995. Peak flow under 50%, or severe breathlessness regardless of reading.

If you use a peak flow meter (we’ll usually suggest one if you’ve had an exacerbation, have difficulty sensing early symptoms, or have moderate-to-severe asthma), your personal best is established across 2 weeks of twice-daily monitoring when you’re well. The green/yellow/red zones on your action plan are anchored to that personal best, not to a published “normal.”

If you don’t have a written plan, please ask for one at your next visit. The plan is most useful when it’s personalised to your usual medications and your typical patterns — not a generic leaflet.

How controlled is your asthma? — the GINA 4-question check

A quick way to judge how well-controlled your asthma actually is (as opposed to how used to the symptoms you’ve become). Over the past 4 weeks, ask yourself:

1. Have you had daytime asthma symptoms more than twice a week?
2. Have you had any night waking due to asthma?
3. Have you needed to use your reliever for symptoms more than twice a week (not counting pre-exercise doses)?
4. Has your asthma limited your activity — work, school, exercise, daily life?

Scoring:

• 0 yes answers → well-controlled — carry on, review periodically
• 1–2 yes → partly controlled — your treatment plan may need adjusting
• 3–4 yes → uncontrolled — please come in, don’t just push through it

This tool was developed by GINA and is widely used in primary care. We do this check at every follow-up visit. If you’re using a home symptom diary, running the GINA questions yourself between visits can flag when you need to come back sooner.

Triggers and what influences control — the BREATHE checklist

Good asthma care looks at more than just the inhaler. The ACE guideline uses the acronym BREATHE to remember what to assess at each review:

• Beliefs, knowledge, and attitudes — misconceptions about asthma or steroids are common and worth addressing
• Recent asthma treatment — what you’re actually using (and how often) vs what was prescribed
• Effects of asthma — on quality of life, work, sleep, school, exercise
• Adherence — be honest with us. If a plan isn’t being followed, we’d rather know why and adjust than assume it’s working.
• Triggers — dust mites, pet dander, cockroach exposure, pollens, haze, tobacco smoke (including secondhand), occupational exposures, exercise, cold air, viral infections, certain medications (aspirin/NSAIDs, non-selective beta-blockers)
• History of asthma — including previous severe attacks or ICU admissions (a strong predictor of future severe attacks)
• Existing comorbidities or medications — allergic rhinitis, sinusitis, GORD, obesity, obstructive sleep apnoea, mental health conditions

Practical trigger-reduction measures worth the effort:

• If dust-mite allergy is clear — dust-mite-impermeable mattress/pillow covers, washing bedding in hot water, reducing soft furnishings in bedrooms
• Don’t smoke, and try to be in a smoke-free environment (secondhand smoke matters)
• Plan around the haze season — keep rescue medication accessible, reduce outdoor exercise on bad AQI days
• Annual flu vaccination (which we’ll discuss below)
• Address allergic rhinitis — well-controlled nose = well-controlled lower airway for many people

When things worsen — exacerbations

Signs that your asthma is moving out of the green zone:

• Reliever use more than twice a week (beyond pre-exercise doses)
• Waking at night with cough or breathlessness, even once or twice
• Daytime symptoms most days
• Inability to do normal activities (stairs, walking pace) without getting breathless
• Peak flow readings dropping from your personal best (if you monitor)

Early action matters. A flare caught and treated early — by stepping up ICS-containing treatment, sometimes adding a short course of oral prednisolone under our guidance — is far more likely to settle than one ignored for a week. Please come in sooner rather than later if you’re noticing any of the above.

Come in urgently (or call 995 / go to A&E) if you have:

• Severe breathlessness — unable to speak in full sentences, or struggling to breathe at rest
• Reliever not working — using it more frequently than every 4 hours without relief
• Rapidly worsening symptoms
• Blue lips or fingertips, or confusion
• A sense that something is seriously wrong

Severe asthma attacks can deteriorate quickly. Don’t drive yourself if it’s bad — take a taxi, call a friend, or call 995.

A short note on children with asthma

Most asthma principles for adults apply to children, with a few differences. For a fuller parent-facing guide, see Asthma in children — what parents need to know. Briefly:

• Children under 6 are usually managed on daily low-dose ICS or a leukotriene receptor antagonist (montelukast/Singulair), with a SABA reliever. The MART approach is not generally used in this age group.
• Children 6–11 can use ICS-formoterol MART as an option, but the algorithm is slightly different from adults.
• Spacers with a face mask are essential for young children using a pMDI.
• School asthma plans — give a copy of the asthma action plan to the school/childcare. Most schools can also hold a spare reliever inhaler.
• A note on montelukast (Singulair) — Singapore’s Health Sciences Authority has issued an advisory about possible neuropsychiatric effects (mood change, agitation, occasionally suicidal thoughts). It remains a useful medication for some children, but we discuss the risks and ask caregivers to watch for any mood or behavioural changes.

Paediatric asthma often improves significantly through adolescence. But the earlier it is well-controlled, the more likely that trajectory is to be smooth.

Comorbidities that affect asthma control

Several conditions commonly travel with asthma and can make it harder to control. Treating them usually improves breathing as well:

• Allergic rhinitis (runny nose, post-nasal drip, itchy eyes) — a nasal corticosteroid spray is often the single most useful add-on for an adult whose asthma isn’t quite controlled
• Gastro-oesophageal reflux (GORD) — symptomatic reflux can worsen cough and night-time asthma, and treating it helps. Empirical acid-suppression treatment without reflux symptoms doesn’t reliably improve asthma, so we treat GORD only when it’s clinically present
• Obesity — weight reduction often improves asthma outcomes meaningfully
• Obstructive sleep apnoea — common in middle-aged adults with asthma and worth screening for
• Smoking (including vaping) — makes ICS less effective and worsens long-term outcomes
• Anxiety and depression — genuinely impact both asthma symptoms and self-management; worth asking about

Regular follow-up — and why it matters

Patients with well-controlled asthma often stop coming for review — which sounds sensible but usually isn’t. A few reasons we recommend at least two visits a year, and more after a flare-up or treatment change:

• Guidance has evolved, particularly around ICS-formoterol — your plan from 5 years ago may no longer be the best option
• Inhaler technique drifts — a one-minute check at review catches errors early
• Adherence drifts too — a non-judgmental conversation often improves this
• Comorbidities develop — a change in nose, reflux, weight, or mood can quietly worsen your asthma
• Severe attacks are more predictable than most people realise — we can spot risk features (high SABA use, recent exacerbation, inadequate preventer) and pre-empt them

The ACE guideline recommends:

• Follow-up 1–2 weeks after an exacerbation
• Follow-up 1–3 months after starting or changing treatment
• Every 1–3 months for patients at higher risk of poor outcomes
• At least twice a year for everyone else

Vaccinations

Patients with asthma should be up to date on:

• Annual influenza (flu) vaccination — respiratory viruses trigger many asthma exacerbations
• Pneumococcal vaccination — reduces risk of serious respiratory infection
• COVID-19 boosters as recommended
• Tdap (tetanus/diphtheria/pertussis) every 10 years

We review vaccinations at every visit, not just annually, to avoid gaps. Many are subsidised under the National Adult Immunisation Schedule (NAIS) and the National Childhood Immunisation Programme (NCIP) — please ask what you’re due for.

The Singapore context — programmes that support you

• Healthier SG Chronic Tier (effective February 2024) — patients enrolled with us can buy common asthma medications (ICS, ICS-LABA, SABA, spacers) at prices similar to polyclinic prices.
• Community Health Assist Scheme (CHAS) — means-tested subsidies for consultations and selected medications at participating GP clinics. Pioneer Generation and Merdeka Generation cardholders have additional benefits. More at chas.sg.
• MediSave — usable for chronic disease consultations and selected medications, up to the annual withdrawal limit (currently $500, rising to $700 / $1,000 from January 2027).
• Primary Care Networks (PCN) — KTMC is part of the Class PCN, which supports nurse counselling, spirometry arrangements, and chronic disease registry tracking.

Get in touch

Joo Chiat — 172 Joo Chiat Road, #01-01, Singapore 427443 · Tel 6920 1952

Punggol — 658 Punggol East, #01-04, Singapore 820658 · Tel 6312 4589

Email — admin@ktmc.sg

References

Guidelines and national programmes

• Agency for Care Effectiveness (ACE). Asthma — optimising long-term management with inhaled corticosteroid. ACE Clinical Guidance, Ministry of Health, Singapore. October 2020. ace-hta.gov.sg
• Global Initiative for Asthma (GINA). Global Strategy for Asthma Management and Prevention — 2026 update. ginasthma.org
• British Thoracic Society / NICE / SIGN. Joint guideline for the diagnosis, monitoring and management of chronic asthma in adults, adolescents and children over 12 years. 2024. nice.org.uk
• Health Sciences Authority Singapore. Drug Safety Information No. 71 — advisory on montelukast and neuropsychiatric effects.
• Ministry of Health Singapore. National Adult Immunisation Schedule (NAIS). healthhub.sg

SABA overuse and safety

• Nwaru BI, Ekström M, Hasvold P, Wiklund F, Telg G, Janson C. Overuse of short-acting β2-agonists in asthma is associated with increased risk of exacerbation and mortality: a nationwide cohort study of the global SABINA programme. Eur Respir J. 2020;55(4):1901872. ersjournals.com
• MHRA (UK). Short-acting beta-2 agonists (SABA): reminder of the risks from overuse in asthma. Drug Safety Update, 2024. gov.uk

This information is for general education only and is not a substitute for medical advice. Asthma management must be individualised to your symptom pattern, triggers, and response to treatment — please speak with our team about what’s right for you. v1.0 · April 2026 · Review due April 2028.