Hay Fever (Allergic Rhinitis) — NZ Condition Guide | KiwiMeds

What is Hay Fever?

Hay fever (allergic rhinitis) is an allergic reaction to airborne substances — most commonly pollen, dust mites, pet dander, and mould spores. It causes inflammation of the lining of the nose. Hay fever is extremely common in New Zealand — around 1 in 5 New Zealanders is affected. Seasonal hay fever is triggered by pollens (typically from grass, trees, and weeds during spring and summer), while perennial (year-round) allergic rhinitis is usually triggered by dust mites, pet allergens, or mould.

Symptoms

Hay fever symptoms include a runny or blocked nose, sneezing (often in fits), itchy and watery eyes (allergic conjunctivitis), itchy nose, mouth, or throat, reduced sense of smell, and post-nasal drip. Symptoms can significantly impair quality of life — affecting sleep, work performance, and concentration. Hay fever often occurs alongside asthma and eczema.

Causes and Risk Factors

Hay fever is caused by an IgE-mediated allergic response — the immune system overreacts to harmless airborne substances, triggering the release of histamine and other inflammatory chemicals. Risk factors include family history of allergies, asthma, or eczema, growing up in an urban environment, and possibly early childhood antibiotic exposure. New Zealand’s high grass pollen counts — particularly from ryegrass in spring — are a significant cause of hay fever.

Diagnosis

Hay fever is usually diagnosed based on symptoms and their seasonal pattern. Allergy testing (skin prick testing or blood tests for specific IgE) can identify specific triggers and is useful if symptoms are severe or if immunotherapy is being considered.

Treatment in New Zealand

Treatment is stepped according to severity. Allergen avoidance where possible is helpful but not always practical. Medications include non-sedating oral antihistamines (cetirizine, loratadine, fexofenadine — available over the counter), intranasal corticosteroid sprays (fluticasone, mometasone, budesonide — very effective for nasal symptoms, now available over the counter), decongestants (for short-term use only), and antihistamine eye drops for eye symptoms. For severe allergic rhinitis not controlled by medications, allergen immunotherapy (allergy shots or sublingual drops/tablets) may be considered — it can provide long-term desensitisation.

NZ-Specific Information

New Zealand grass pollen season typically runs from September to February, peaking in October–December. Pharmac funds some antihistamines and nasal steroid sprays on prescription. Over-the-counter options (cetirizine, fluticasone nasal spray) are widely available at pharmacies. The Asthma + Respiratory Foundation NZ tracks pollen counts and provides NZ-specific hay fever information.

Frequently Asked Questions

Do antihistamines cause drowsiness? Older antihistamines (promethazine, chlorphenamine) cause significant drowsiness. Newer antihistamines (cetirizine, loratadine, fexofenadine) are non-sedating for most people. How quickly do nasal steroid sprays work? They take several days to reach full effect — they should be used regularly throughout the pollen season, not just when symptoms are bad. Can children take antihistamines? Yes — cetirizine and loratadine are available in children’s formulations.

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 — Vitamin D deficiency is associated with higher rates of allergic sensitisation and increased hay fever severity. Supplementation where deficiency is present may modulate Th2-mediated allergic immune responses.
• Quercetin — Quercetin stabilises mast cells, reducing histamine release. At 500 mg twice daily, it provides a natural antihistamine-like effect and may reduce allergic inflammation, particularly when started 4–6 weeks before pollen season.
• Butterbur (PA-free extract) — PA-free butterbur extract has demonstrated equivalence to cetirizine in randomised trials for hay fever symptom reduction. It provides antihistamine benefit without sedation. Only use PA-free certified products.
• Probiotics — Emerging evidence supports probiotic supplementation (particularly Lactobacillus and Bifidobacterium species) for modulating allergic immune responses and reducing hay fever symptom severity, likely through gut-immune axis effects.
• Omega-3 Fatty Acids — Omega-3 supplementation may reduce the severity of allergic airway inflammation by shifting the balance from pro-inflammatory to anti-inflammatory eicosanoid production.

Relevant Vaccinations

Individuals living with hay fever (allergic rhinitis) 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) — Respiratory viral infections worsen hay fever symptoms and upper airway inflammation. Annual influenza vaccination reduces this burden.
• Allergen immunotherapy (allergy shots/sublingual drops) — While not a traditional vaccine, allergen immunotherapy (available in NZ) is the only treatment that modifies the underlying allergic disease, with evidence for durable symptom remission. Discuss with an allergist or ENT specialist.

Dietary Guidance

Evidence-based dietary modifications play a meaningful role in the management of hay fever (allergic rhinitis). 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.

• Local honey (raw) — Consuming locally sourced raw honey is popularly believed to desensitise to local pollen allergens. While evidence is limited, it carries no harm and may provide modest benefit for those allergic to locally produced pollen types.
• Quercetin-rich foods (capers, red onion, apples, berries) — Dietary quercetin provides natural mast cell-stabilising antihistamine-like benefit.
• Omega-3 rich foods (oily fish) — Anti-inflammatory omega-3 intake may reduce the severity of seasonal allergic inflammation.
• Vitamin C-rich foods (kiwifruit, capsicum, citrus) — Vitamin C has antihistaminic properties and antioxidant activity that may reduce nasal inflammation. Kiwifruit is an excellent NZ source of vitamin C.
• Avoid: known food cross-reactive allergens — Some people with pollen allergy experience oral allergy syndrome (itching in mouth/throat) from raw fruits and vegetables cross-reactive with their specific pollen allergen (e.g., birch pollen allergy → apple, cherry, carrot). Cooking these foods usually eliminates the reaction.

Related Conditions & Medications

Related medications: Cetirizine, Loratadine. Related conditions: Asthma, Eczema.