Clinically reviewed by Dr Muhammad Najam-Ul-Arfeen, General Practitioner
Bachelor of Medicine and Bachelor of Surgery (MBBS)
AHPRA-registered
Last updated: 6 September 2026
What Is Asthma?
Asthma is one of the most common chronic respiratory diseases, affecting the airways and making breathing difficult. In someone with asthma, these airways are more sensitive than usual and react to certain triggers by becoming inflamed, narrowed, and often filled with excess mucus. This combination, airway inflammation and bronchoconstriction (the tightening of the muscles around the airways), is what makes breathing feel difficult during a flare-up.
It is a fluctuating condition: for much of the time, especially when well managed, symptoms may be minimal or absent entirely. At other times, triggered by an allergen, a cold, exercise, or another factor, symptoms can flare noticeably, ranging from mild breathlessness to a serious asthma attack requiring urgent treatment.
Types of Asthma
Asthma isn’t uniform. It shows up differently depending on what’s driving it and when it started.
- Allergic asthma: triggered by pollen, dust mites, mould, or pet dander; often linked to hay fever or eczema and tends to be seasonal.
- Non-allergic asthma: triggered by infections, cold air, pollution, smoke, stress, or medications, with no clear allergic cause, making it harder to pin down.
- Exercise-induced asthma (EIB): airway narrowing from physical activity, especially in cold or dry air; can occur alongside broader asthma or on its own. See our guide on asthma and exercise.
- Occupational asthma: triggered by workplace exposure (flour dust, chemicals, wood dust, cleaning agents); symptoms easing on days off is a key clue.
- Childhood-onset asthma: begins early in life, often linked to allergic triggers and family history; may improve with age or persist into adulthood.
While it impacts millions globally, particularly in developed countries like Australia, many people still ask a critical question: What is the main cause of asthma?
What is the main Cause of Asthma? (Triggers)
Asthma doesn’t have a single, universal cause. Instead, it’s the result of a complex interaction between genetic predisposition, environmental exposure, and immune responses. Some individuals are born with a higher bronchial sensitivity, making them more susceptible to asthma triggers such as allergens or viral infections. Others develop the condition later in life due to environmental factors like air pollution, chemical irritants, or prolonged exposure to indoor allergens such as dust mites, mould, or pet dander.
Genetic and Environmental Influences
It develops from a mix of genetic and environmental factors that aren’t fully understood, but its triggers are well known: pollen, dust mites, mould, pet dander, cold air, air pollution and bushfire smoke, cigarette smoke and vaping, and respiratory infections.
Common Symptoms of Asthma
Asthma symptoms can vary considerably between individuals, and even from one flare-up to the next in the same person. The most common signs include:
- Wheezing, a whistling sound when breathing, especially on exhaling
- Shortness of breath, even during activities that wouldn’t normally cause it
- Chest tightness or a feeling of pressure across the chest
- A persistent cough, particularly at night, early morning, or after exercise
- Increased symptoms during colds, flu, or other respiratory infections
- Fatigue related to disrupted sleep or the extra effort of breathing
How Is Asthma Diagnosed?
Diagnosis typically combines a symptom history and physical exam with lung function testing, spirometry to measure airway narrowing and response to reliever medication, peak flow monitoring at home to track patterns, FeNO testing to gauge airway inflammation, and allergy testing where allergic asthma is suspected. Complex cases may be referred to a respiratory specialist.
Reliever vs Preventer Inhalers: Understanding Your Asthma Medication
Reliever Inhalers
Reliever inhalers (commonly blue or grey in Australia) contain a bronchodilator medication, most often salbutamol, which works quickly to relax the muscles around the airways, easing symptoms within minutes. Use relievers as needed, during symptoms or before exercise if advised, and during asthma first aid.
Preventer Inhalers
Asthma Preventer inhalers (commonly brown, orange, or purple, depending on the brand) contain an inhaled corticosteroid, which works gradually over time to reduce the underlying airway inflammation that drives asthma symptoms. These are taken regularly, usually daily, whether or not symptoms are present. They do not provide immediate relief during a flare up, which is exactly why using the correct inhaler at the right time matters.
Some people are prescribed a combination inhaler under MART (Maintenance and Reliever Therapy) or AIR therapy (Anti-inflammatory Reliever), where one inhaler is used both regularly and for symptom relief. Your GP will advise which approach suits your pattern
Risk Factors for Asthma
Understanding risk factors helps with early identification and prevention. Common risk factors include:
- Respiratory allergies or allergic rhinitis
- Living in areas with high air pollution
- Regular exposure to inhaled irritants (e.g. fumes, smoke)
- Obesity, which can affect lung function
- A history of viral infections during infancy
- Occupational hazards (e.g., farming, painting, cleaning)
In addition to environmental and genetic factors, certain lifestyle habits, like smoking or living in mouldy environments, can significantly increase asthma risk.
Proper Asthma Inhaler Technique
Incorrect inhaler technique is extremely common, and can mean a significant portion of each dose never reaches the lungs. General good practice includes:
- Shaking the inhaler before use (for pressurised metered-dose inhalers).
- Using a spacer device where recommended; this improves medication delivery considerably and reduces mouth/throat side effects.
- Breathing out fully before inhaling the dose, then breathing in slowly and steadily while activating the inhaler.
- Holding your breath for around 10 seconds after inhaling, where possible, before breathing out.
- Rinse your mouth after using a preventer inhaler to reduce the risk of oral thrush.
If you’re not confident your technique is correct, it’s genuinely worth asking a GP or pharmacist to check it directly; this is one of the simplest, highest-impact things you can get reviewed.
Common Asthma Medication Side Effects
Relievers can occasionally cause tremor, a faster heartbeat, or restlessness with frequent use (itself a sign asthma isn’t well controlled). Preventers are generally well tolerated; the main risks are oral thrush and hoarseness, both reduced by using a spacer and rinsing after each dose.
If you have an existing diagnosis and need a repeat prescription, a telehealth GP consultation can review your control and issue an e-Script directly, without an in-person visit.
How to Get a Repeat Asthma Prescription Online
If you have an existing asthma diagnosis and need a repeat prescription for your reliever or preventer inhaler, an online GP consultation is often the fastest and most convenient option, particularly if your asthma is stable and well-controlled.
A GP can review your current symptoms and control, issue an e-Script sent directly to your phone, and flag if it’s time for an in-person review or a change to your asthma action plan.
What Is an Asthma Action Plan?
An asthma action plan is a written, individualised document developed with your GP, that sets out your regular medications, what to do if your symptoms worsen, and clear steps for responding to an asthma emergency.
Asthma Australia and the National Asthma Council Australia both strongly recommend every person with asthma have a current written action plan, since it takes the guesswork out of decision-making exactly when it’s hardest to think clearly during a flare-up.
How to Get an Asthma Action Plan Online (From a GP)
You don’t need to wait for a routine in-person visit to get or update an asthma action plan, a telehealth consultation with a GP can cover this directly. The GP will discuss your current symptoms, medication, and triggers, assess whether your asthma is well controlled, and provide a written plan that can typically be sent to you digitally, ready to keep on hand, share with family, or provide to a school or workplace.
Asthma First Aid: The 4x4x4 Rule
The nationally recognised protocol for a flare-up or attack, using the reliever (blue/grey) inhaler:
- Sit the person upright and stay calm.
- Give 4 separate puffs (via a spacer if available), with 4 breaths after each puff.
- Wait 4 minutes.
- If there’s no improvement, give 4 more puffs the same way.
- If there’s still no improvement, call 000 immediately, state it’s an asthma emergency, and continue 4 puffs every 4 minutes while waiting.
Call 000 immediately, without waiting through the sequence, if the person can’t speak in full sentences, their lips turn blue, they collapse, or they’re rapidly deteriorating.
What Is the "Rule of 2" for Asthma Control?
The Rule of 2 is a simple, used way to check whether your asthma is well controlled, not just “manageable.” If any of these apply more than twice, it’s a sign your control needs review:
- Using your reliever inhaler more than twice a week (outside of before-exercise use, if that’s part of your plan)
- Waking at night due to asthma symptoms more than twice a month
- Needing to refill your reliever prescription more than twice a year
If any of these sound familiar, it’s a genuine signal to book a GP review, even if you haven’t had a severe attack, good control is about more than just avoiding emergencies.
FAQs
Can asthma develop later in life?
Yes. Adult-onset asthma is increasingly common and can be triggered by long-term exposure to irritants, hormonal changes, or health conditions like GERD.
How can I manage asthma without an inhaler?
Inhaled medication is the standard, most effective asthma treatment, and shouldn’t be avoided without medical guidance. That said, identifying and reducing exposure to your specific triggers, maintaining good indoor air quality, staying up to date with vaccinations against respiratory infections, and following your written asthma action plan all support better control alongside your prescribed treatment; they’re not a substitute for it.
Can I get an asthma puffer prescription online in Australia?
Yes. If you have an existing asthma diagnosis, a telehealth GP consultation can review your current control and issue a repeat prescription via e-Script, without needing an in-person visit.
How do allergic asthma and non-allergic asthma differ?
Allergic asthma is triggered by allergens and involves immune responses. Non-allergic asthma is typically triggered by irritants, infections, or stress and doesn’t involve the same immune pathways.
Can emotional stress cause asthma attacks?
Yes. Strong emotions can act as triggers by causing rapid breathing and airway constriction.
How can HelloGP help manage asthma?
Through online consultations, HelloGP provides access to experienced Australian healthcare providers who assist with diagnosis, developing action plans, and managing symptoms, all without leaving your home.
Need a new action plan, a control review, a repeat prescription, or have symptoms for the first time? HelloGP’s online doctors can help from home, without the wait, covering symptom review, technique checks, action plans, and e-Script repeats.
HelloGP - Disclaimer
This article is for general information only and does not replace professional medical advice. Telehealth is not suitable for emergencies. If you have an emergency or are at immediate risk, call 000 or visit your nearest emergency department.