Asthma — NZ Condition Guide | KiwiMeds

What is Asthma?

Asthma is a common lung condition where the airways become inflamed, narrowed, and produce extra mucus, making it difficult to breathe. New Zealand has one of the highest rates of asthma in the world — around 1 in 8 New Zealanders has asthma, and it is the most common chronic condition in children. While asthma cannot be cured, it can be very well controlled, allowing most people to live fully active lives.

Symptoms

Asthma symptoms include shortness of breath, wheezing (a whistling sound when breathing), chest tightness, and cough — particularly at night or early morning. Symptoms often come and go and may be triggered by exercise, cold air, respiratory infections, allergens (pollen, dust mites, pet dander, mould), tobacco smoke, air pollution, or strong smells. A severe asthma attack is a medical emergency.

Causes and Risk Factors

Asthma is caused by a combination of genetic and environmental factors. It is an inflammatory condition where the airways are hypersensitive and react to triggers that would not affect most people. Risk factors include family history of asthma or allergies, eczema, hay fever, exposure to cigarette smoke (especially in early childhood), respiratory infections in infancy, and living in damp or mouldy homes — a significant issue in New Zealand’s older housing stock.

Diagnosis

Asthma is diagnosed by a doctor based on your symptoms and lung function tests, particularly spirometry (breathing into a device that measures airflow). A trial of bronchodilator medication that relieves symptoms supports the diagnosis. For children under 6, diagnosis relies more heavily on the pattern of symptoms.

Treatment Options in New Zealand

The cornerstone of asthma treatment in NZ is the combination of a reliever inhaler (salbutamol/Ventolin — a blue inhaler, used when symptoms occur) and, for persistent asthma, a preventer inhaler (usually an inhaled corticosteroid such as budesonide or fluticasone, taken daily). Both are fully funded on the Pharmac schedule. The Asthma + Respiratory Foundation NZ provides an Asthma Action Plan — a written plan from your doctor that tells you what to do in different situations. Make sure you have an up-to-date action plan.

NZ-Specific Information

New Zealand’s high asthma rates are partly linked to our housing quality — cold, damp, mouldy homes are asthma triggers. The Healthy Homes Standards (which came into full effect in 2021) require rental properties to meet minimum heating, insulation, and ventilation requirements. Pharmac funds all standard asthma inhalers at $5 per prescription. The Asthma + Respiratory Foundation NZ (asthmafoundation.org.nz) offers free resources and a nurse helpline. Many Māori and Pacific peoples have higher rates of severe asthma — culturally appropriate care is increasingly available.

Frequently Asked Questions

Is my asthma well controlled? Well-controlled asthma means you have symptoms no more than twice a week, rarely wake at night due to asthma, and rarely need your reliever inhaler. If you need your reliever more than twice a week, see your doctor — your preventer may need adjusting. Can I exercise with asthma? Yes. With good asthma control, most people with asthma can exercise normally. Exercise-induced asthma can be prevented by using your reliever inhaler before exercise. Can children outgrow asthma? Some children improve significantly as they get older, particularly those with mild symptoms. However, asthma often returns in adulthood.

Supplements That May Support Management

⚠️ Important: The supplements listed below have varying levels of clinical evidence. They are not a substitute for prescribed medications and should only be considered as adjunctive support under the guidance of a qualified healthcare professional. Always inform your GP or pharmacist before commencing any supplement, as interactions with prescribed medicines are possible.

• Vitamin D — Low vitamin D status is associated with increased asthma exacerbation frequency and severity. Supplementation in deficient individuals reduces the risk of acute exacerbations requiring oral corticosteroids. Evidence is strongest in those with baseline deficiency.
• Magnesium — Magnesium has bronchodilatory properties via calcium antagonism in airway smooth muscle. Intravenous magnesium is used clinically in acute severe asthma. Oral supplementation may reduce airway hyperresponsiveness in deficient individuals.
• Omega-3 Fatty Acids — Omega-3 supplementation has demonstrated modest reductions in airway inflammation and bronchial hyperresponsiveness in some studies, particularly in exercise-induced bronchoconstriction.
• Quercetin — A flavonoid with mast cell-stabilising and anti-inflammatory properties, quercetin may reduce allergic airway inflammation. Doses of 500 mg twice daily have been studied; however, clinical evidence remains preliminary.
• Vitamin C — Some evidence supports a modest protective role for vitamin C (1–2 g/day) in exercise-induced bronchoconstriction. As an antioxidant, it may reduce oxidative stress in asthmatic airways.

Relevant Vaccinations

Individuals living with asthma may benefit from the following vaccinations. Please discuss your vaccination status with your GP or practice nurse, as eligibility and funding through the New Zealand National Immunisation Schedule may apply.

• Influenza (annual) — Influenza is one of the most common triggers of asthma exacerbations and is associated with significant morbidity in people with asthma. Annual vaccination is funded and strongly recommended under NZ guidelines.
• Pneumococcal — People with moderate-to-severe or poorly controlled asthma are at increased risk of pneumococcal lower respiratory tract infection. Vaccination is recommended and funded for high-risk asthma patients in NZ.
• COVID-19 — Respiratory viral infections including COVID-19 can trigger acute asthma exacerbations. Maintaining COVID-19 vaccination is recommended.
• Whooping cough (pertussis booster) — Pertussis infection can be particularly severe in people with pre-existing respiratory conditions. Ensure booster vaccination is current.

Dietary Guidance

Evidence-based dietary modifications play a meaningful role in the management of asthma. The following foods are generally recommended as part of a balanced, condition-appropriate diet. A referral to a registered dietitian may be beneficial for personalised nutritional planning.

• Mediterranean dietary pattern (fruits, vegetables, olive oil, fish) — A Mediterranean dietary pattern is the most studied dietary approach in asthma, with evidence supporting reduced asthma severity and exacerbation frequency, likely through anti-inflammatory mechanisms.
• Oily fish (salmon, mackerel, sardines) — EPA and DHA reduce leukotriene production, which plays a central role in airway inflammation and bronchoconstriction. Regular consumption supports systemic anti-inflammatory activity.
• Fruits and vegetables high in antioxidants — Vitamin C (kiwifruit, capsicum, citrus) and vitamin E (nuts, seeds, avocado) are antioxidants that may reduce oxidative stress in asthmatic airways and modulate inflammatory signalling.
• Limit sulphite-containing foods (wine, dried fruit, processed meats) — Sulphites are a recognised asthma trigger in sensitive individuals. Reading food labels and minimising sulphite intake may reduce symptom burden in those who react to them.
• Turmeric (curcumin) — Curcumin has demonstrated anti-inflammatory properties including inhibition of NF-κB signalling. Preliminary evidence suggests potential benefit in allergic airway inflammation when incorporated into a varied diet.

Related Conditions & Medications

Related medications: Salbutamol (Ventolin). Related conditions: Eczema, Hay Fever.