Allergy Tests

What are the different allergy test methods available?

To understand your allergy concerns, your doctor will first discuss your symptoms and medical history. A physical examination including a complete examination of your eyes, ears, nose, throat, skin and neck will follow.

Based on this information, they will recommend the most appropriate test. Test methods includes Skin Prick Test or IgE blood test or Patch Test or Food Challenge.

Limitations of Skin Prick Test

  • Oral and nasal antihistamines must be stopped one week prior to testing
  • SPT is not suitable for patients with dermatits (uticaria) or widespread skin lesion
  • The reliability and interpretation of the test result is heavily dependent on the skill of the tester
  • While rare, SPT can trigger an anaphylactic reaction

    • What is an IgE blood test?

    An IgE test, or Immunoglobulin E test, is a blood test used to measure the level of IgE antibodies in your blood. IgE antibodies are produced by your immune system in response to allergens. Elevated levels of IgE can indicate an allergic reaction.

    Advantages of doing an IgE blood test:

  • More sensitive than skin prick tests for certain allergens
  • Useful for people with skin conditions that interfere with skin prick tests
  • No risk of anaphylactic reactions
  • Allows tracking changes of IgE over time to monitor allergic reaction

    Limitations of IgE blood test:
  • More expensive
  • Results are not ‘immediately’ available

    • What is a Patch test?

    Patch test is used to diagnose contact dermatitis, an allergic reaction to substances that touch your skin. Small patches containing allergens are applied to your back. The patches are left on for 48 hours, then removed and checked for a reaction.

    What is an Oral Food Challenge (or Food Challenge)?

    Food Challenge involves gradually introducing a suspected food allergen into your diet under medical supervision. It is used to confirm food allergies when other tests are inconclusive.

    Limitations of Oral Food Challenge

  • Only one food can be tested at each appointment
  • There is a risk of anaphylactic reaction, hence it should always only be conducted under the strict medical supervision of a clinician

    Remember:
  • It's important to consult with a healthcare professional to diagnose and treat allergies.
  • Self-diagnosis and treatment can be dangerous, especially for severe allergies.
  • If you experience a severe allergic reaction, seek immediate medical attention.