Allergy Basics

Fluffy kittens, lush lawns and shady trees are just some of the simple pleasures in life which can cause your allergy symptoms to flare up. Therefore, it is important for you to identify the causes of your allergy and what to do about them, so you can enjoy more of the world around you.

What Are Allergies?

An allergy occurs when the immune system mistakenly attacks foreign substances that are generally safe such as dust mites , mold , pet dander and pollen for something dangerous and attacks it. These typically harmless substances are also known as allergens.

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What Causes Allergy Symptoms?

Allergens can enter your body when you take a breath, or when rub your nose or eyes, and cause your immune system to trigger a hypersensitive reaction. Therefore, in order to do away with the substances that your body perceives to be harmful, it produces antibodies such as the inflammatory mediator known as histamine .

When the mast cells in your body release histamine, it triggers an allergic reaction which includes symptoms such as a runny nose, sneezing, itchy or watery eyes, an itchy nose or throat, nasal congestion and sinus pressure.

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To rid itself of an allergen , or allergens, your body experiences a number of allergic reactions which, collectively, are known as an allergic cascade.* This causes your body to then release a few different inflammatory mediators. If an allergen, or allergens, enter your body, the mast cells in your body will then release an inflammatory mediator known as histamine . Histamine attaches to the receptors on blood vessels, causing them to dilate. In addition to that, histamine also binds to other receptors located in the nasal tissues, causing allergy symptoms which include swelling, as well as an itchy and runny nose.

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How Clarityn ® Helps Reduce Allergy Symptoms

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*Like those from pets, pollen , dust and mold .

Clarityn® is an antihistamine that is able to mitigate the allergic cascade triggered by an allergen , or allergens.


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How Are Allergies Diagnosed?

In some cases, it could be easy for you to determine the triggers of an allergic reaction. For example, if you sneeze more frequently when you walk into a dusty room or loft, or if you experience allergy symptoms that start to act up when you are exposed to allergens.

But if you’re unsure as to what the cause of your allergy is, you can opt to see an allergist. An allergist is specially trained to identify allergy triggers, and how to avoid them. During an appointment, the allergist may: 1

  • Take down your personal information and medical history to help you understand your symptoms, and their possible causes better. Therefore, it is recommended for you to jot down some notes about your family history, lifestyle and potential triggers before your appointment.1
  • Perform a physical examination, paying special attention to your nose, throat, eyes, ears, chest and skin.1
  • Conduct a skin test, patch test and/or blood test to help determine the allergens that you are particularly sensitive to.1
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Asia Pacific region has the highest prevalence of Allergic Rhinitis compared to the other regions in the world.2

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Reducing Your Exposure to Airborne Allergens

Apart from using Clarityn® to help mitigate severe allergy symptoms, it is also important for you to minimise your exposure to allergens. Read on below for a few simple tips on how to reduce your exposure to indoor and outdoor allergy triggers effectively.


A haze is an atmospheric phenomenon which causes dust, smoke and other dry particulates to impair the clarity of the sky. These aerosols usually arise from complex chemical reactions that occur as a result of sulphur dioxide gases emitted during combustion converting into small droplets of sulphuric acid. In Southeast Asia, the haze is characterised by a large-scale air pollution problem that is particularly debilitating from July and October. As a result, the haze causes adverse health and economic impacts in countries such as Singapore, Malaysia and Indonesia, and to a lesser degree, the Philippines and Thailand.


Indoor Allergies

Indoor allergies are caused by immune system reactions to allergens such as dust mites , mold and pet dander. An indoor allergy can be experienced at any time during a year, but could be experienced more frequently during the monsoon season, when people spend more time indoors. As with outdoor allergies , it could be difficult for you to avoid being exposed to allergens. However, do take comfort in knowing that implementing some of these simple allergy prevention tips can help you to do away with allergy triggers and enable you to enjoy the comforts of your home all-year round..



  1. Allergy Diagnosis. Asthma and Allergy Foundation of America. Accessed November 30, 2017.
  2. Bousquet J, Khaltaev N, Cruz AA, et al. Allergic Rhinitis and its Impact on Asthma (ARIA) 2008 Update (in collaboration with the World Health Organization, GA2LEN* and AllerGen **). Allergy . 2008; 63 (86): 8–160.