Skin Tests are used to confirm clinical sensitivity induced by aeroallergens, foods, some drugs, a few chemicals, and hymenoptera venom.
Indicated in following diseases:
- Allergic Rhinitis
- Food Allergy
- Atopic dermatitis
- Hymenoptera hypersensitivity
Factors affecting skin test
- Age-infancy or old age
- Sex -no difference
- Race-wheeling more in blacks
- Circadian rhythm peak in late evening
- Seasonal variation pollen allergy
- Skin condition-skin eczema
- Other condition-diabetic neuropahthy
*Skin test can be performed even at one month of age
Skin prick testing is done demonstrates an allergic response to a specific allergen. SPT can help to confirm the presence of an allergy to pollen, food, dust, mites, moulds and animal dander’s. SPT is a simple, safe and quick test, providing results within 15-20 minutes. This will enable you to receive a diagnosis and management plan at your appointment.
The skin prick test introduces a tiny amount of allergen into the skin, eliciting a small, localized allergic response, in the form of a wheal (bump) and flare (redness) at the site of testing. These tests can be carried out on all age groups, including babies. The test allergens are selected following a discussion with your clinician and based on your history.
The patient needs to avoid taking anti-histamines and certain other medications before the test.
Antihistamine for example cetrizine,loratidine,fexofenadine should stop at least 5 to 7 days before the testing
Tricyclic anti depressant ( doxepine)and atypical antipsychotic drugs (ex.risperidone,olanzapine,ziprasidone) should be taper down if required a wk before the testing.
Beta blockers should be stopped in all instances 24 hour before the testing
Potential Risks of Non-Specialist Care
- Misinterpretation of test results
- Over diagnosis
- Over prescription of meds and treatments
- Costly and unnecessary allergen avoidance