Allergic Rhinitis

Allergic rhinitis represents a chronic inflammatory response affecting the nasal passages when the immune system overreacts to harmless substances such as pollen, pet dander, or mould. When exposed, the body mistakenly identifies these allergens as threats and triggers an immune response. This leads to the release of histamine and other chemicals, causing symptoms such as sneezing, nasal congestion, runny nose, itchy eyes, and postnasal drip.

In Singapore, allergic rhinitis appears in two forms. Seasonal allergic rhinitis is less defined due to the tropical climate, with some allergens present year-round. Perennial allergic rhinitis is more common, triggered by indoor allergens like dust mites and mould, which thrive in warm, humid environments and are recirculated by air conditioning systems.

Singapore’s tropical climate and urban lifestyle contribute to year-round exposure to a variety of allergens. This combination of indoor and outdoor allergens makes allergic rhinitis a persistent issue in the country.

• House Dust Mites – The main cause of allergic rhinitis in Singapore, they thrive in humid conditions and are commonly found in bedding, carpets, and upholstery.
• Pollen – These allergens are released sporadically by tropical plants like Casuarina, Acacia, and palms. Urban landscaping creates pollen hotspots in residential and recreational areas.
• Mould Spores – They flourish in moist, poorly ventilated spaces such as bathrooms and kitchens. Air conditioning units with dirty filters or clogged drains can spread mould indoors.
• Pet Dander – Cats and dogs shed microscopic skin flakes that trigger allergies. With relaxed pet ownership rules in public housing, exposure is increasing.
• Cockroach Allergens – Droppings, body parts, and shed skin from cockroaches are common triggers, especially in densely populated or poorly maintained areas.
• Indoor Air Pollution – Emissions from cooking, cleaning agents, and building materials add to the allergen load in air-conditioned indoor environments, where residents spend about 90% of their time.

Allergic rhinitis is often mistaken for a common cold or sinus infection, leading many to delay proper treatment. Recognising the symptoms early can help manage discomfort, improve sleep and concentration, and prevent complications such as asthma or chronic sinusitis.

Common symptoms include:

• Nasal congestion
• Frequent sneezing
• Itchy nose, throat, and palate
• Clear, watery nasal discharge
• Postnasal drip and persistent cough
• Itchy, watery, or red eyes
• Fatigue and poor sleep
• Dark circles under the eyes (allergic shiners)

Diagnosing allergic rhinitis requires a careful combination of medical expertise, patient insight, and appropriate diagnostic tools. Because its symptoms often mimic other conditions, a proper diagnosis is critical for effective treatment.

• Skin Prick Test
  During the test, small droplets of allergens, such as dust mites and pollen, are placed on the skin, usually on the forearm. The skin is then gently pricked to introduce the allergens just below the surface. A positive reaction appears within 15 to 30 minutes, typically as a raised, itchy bump, similar to a mosquito bite.
• Radioallergosorbent Test (RAST)
  RAST is particularly helpful for patients with eczema, sensitive skin, or those who are taking medications like antihistamines, which could interfere with skin tests. It is also preferred for younger children or anxious patients who may not tolerate skin pricking. Results are typically available within two weeks.

Managing allergic rhinitis involves various approaches that balance symptom relief with long-term control. Treatment depends on the symptoms, their severity, the patient’s age, and any underlying medical conditions.

• Antihistamines – Modern non-sedating and over-the-counter antihistamines are widely used for allergic rhinitis symptoms. These drugs effectively block histamine receptors, curbing symptoms like sneezing, itching, and a runny nose.
• Decongestants – Decongestants relieve nasal and sinus congestion by shrinking blood vessels in the nasal tissues. They come as oral tablets or nasal sprays, and should only be used short term.
• Immunotherapy – Allergy shots gradually expose the body to increasing amounts of allergens, helping the immune system build tolerance over time. The treatment is typically administered weekly or monthly for 3 to 5 years, but offers a chance at lasting relief.
• Allergen Avoidance – This treatment is highly effective when done consistently with smart strategies, such as cleaning, humidity control, and maintaining air quality. The goal is not perfection but minimising daily exposure, which can significantly reduce flare-ups.

Led by highly trained and experienced ENT specialists Dr Paul Mok and Dr Lau Hung Tuan, our clinic takes a comprehensive approach to allergic rhinitis treatment. We will identify your specific triggers, assess your nasal and airway anatomy, and design a personalised treatment plan using reliable diagnostics to improve your sleep, focus, and overall quality of life.

Will my allergic rhinitis ever go away completely?

Some children may outgrow allergic rhinitis during adolescence as their immune systems mature, and some even achieve complete symptom resolution by adulthood. However, for many, once an allergy develops, it often presents as a chronic condition that persists throughout life.

When do I need to see a doctor for allergic rhinitis?

You should check in with your doctor if your allergic rhinitis is not relieved by over-the-counter medicines and you experience:

• Persistent sneezing
• Congestion
• Runny nose
• Itching that lasts more than 10 days

Does exercise help with allergic rhinitis?

Yes, especially when you choose the right type: moderate, low-impact, or well-planned intervals, ideally indoors or when allergen counts are low. This way, you get boosted circulation, reduced inflammation, and improved symptoms without unexpected flare-ups.

Can I prevent allergic rhinitis naturally?

While natural remedies can significantly ease symptoms and potentially reduce your reliance on medications, they should only complement, not replace, your prescribed treatment plan. Always let your doctor guide you, especially if your symptoms persist or if you are considering natural remedies as part of your care.

How long does allergic rhinitis last?

Allergic rhinitis can last as long as you are exposed to your trigger. Without breaking that exposure, symptoms can stretch from days into weeks or even months.