Allergic Rhinitis – Triggers. Diagnosis and Treatment

What is Allergic Rhinitis

It Is a condition where the patient suffers from nasal symptoms such as runny nose, blocked nose, nose itchiness or sneezing that is triggered by substances known as allergens. It is a very common condition and affects up to 13.1% of Singaporeans.

Symptoms and diagnostic criteria

The symptoms of allergic rhinitis are

• Nasal running, nasal congestion, sneezing and itching
• Itchy throat
• Itchy eye or teary eyes

If you have

• 2 or more of these symptoms
• For more than an hour a day
• For more than 2 weeks,

it is diagnostic of allergic rhinitis.

Triggers of Allergic Rhinitis

Common triggers in different categories :

Home triggers

• House dust mites
• Infestations like cockroaches or mice
• Pets

Food triggers

• Milk
• Egg white
• Soy and nuts
• Fish

Occupational or work triggers

• Dust or cement at construction site
• Flour at the bakery

Seasonal triggers

• Pollen or mould pores during certain seasons of the year. In such cases, the sufferers have symptoms of allergic rhinitis only during that particular season like spring for example

Allergic rhinitis tends to run in the family and Is strongly associated with other allergic conditions like :

• Asthma
• Allergic conjunctivitis
• Eczema

Allergic rhinitis can also lead to more serious infective conditions like sinus infections and ear infections.

Diagnosis

In most cases, the diagnosis is achieved through a detailed history and physical examination by your doctor. If we wish to find out exactly what type of allergen can trigger your symptoms , then further tests can be done.

• A skin prick or patch test. Some of the common environmental allergens like house dust mites, cats and dog dander, cockroach, mould, grass and tree pollens can be applied onto your skin and results may be available within 20-30minutes.
• Intradermal provocative food test. This is a test which involves injecting small amounts of food extracts Into the upper arm and measuring the body’s reaction. This test is done more for food triggered rhinitis.

After a diagnosis is made, treatment can then be started.

Treatment

Treatment is generally divided into a few steps.

Step 1: Allergen avoidance

If you are able to identify the triggers to your allergic symptoms, avoid them. Decluttering your home and avoid having carpets. Vacuuming and mopping instead of sweeping.

Using Hepa filters at home to reduce dust and other pollutants.

Allergen proofing bed sheets and washing them with hot water weekly to reduce dust mites

Step 2: Antihistamines

Antihistamines provide relief by controlling the symptoms of allergy by neutralising the effect of the histamine released into the blood stream during an allergic reaction. 

These medications are safe for children as well. Examples includes chlorpheniramine, Zyrtec and telfast. Use them periodically when required to reduce allergic rhinitis symptoms.

Step 3: Intranasal steroids

These medications are very effective in reducing symptoms associated with allergic rhinitis. They work best when used continuously with maximal effect seen after 2 weeks.

Nasal steroids are very safe as they are designed to act in the nose with minimal absorption into the body.

It can be used in children as young as 3 years old.

Sometimes, adjunctive treatment can also be used in the short term to reduce symptoms. Such as decongestant nasal spray and antihistamine eyedrops. However, these medications may cause side effects in the long run and may make symptoms worse once they are stopped. As such, the recommendation will be a short 5 days usage at any one time.

If these still do not work, a referral to an allergist may be necessary to see if other treatment like immunotherapy or other specialised medications need to be started.