Frequently Asked Questions

Why is allergy testing important?
Almost 1 in every 4 Irish people has some type of allergy. However not everyone will be sufficiently troubled to require medical intervention. Allergy is on the increase, probably because of environmental and dietary changes.
Finding out what you are allergic to is an important first step to effective allergy treatment. Today allergy tests are more convenient and accurate than ever before. When combined with a detailed medical history, allergy testing can identify the specific things that trigger your allergic reactions.

Who can be tested for allergies?
Adults and children of any age can be tested for allergies.

How are allergy tests done?
Allergy testing can be done as skin tests or as blood tests. Usually, allergy tests are done under the guidance of an allergy specialist.

How long does it take to get skin test results?
Skin testing is fast and positive reactions usually appear within 20 minutes. Sometimes redness and swelling can occur several hours after skin testing. The delayed reaction usually disappears in 24 to 48 hours, but should be reported to the allergy doctor or nurse.

Is skin testing painful?
Skin tests cause little or no pain. However, positive reactions cause annoying itching red bumps which look and feel like mosquito bites. The itching and bumps are gone usually within thirty minutes. We now use Comforten multiple allergen testing which makes the procedure quick, considerably less painful and much more suitable for children.

Does medicine interfere with allergy skin tests?
Before attending for an allergy test you must NOT have taken tablets or liquid of anti-histamine medicines (please note, these are put into many cough bottles). Ideally you should not be using steroid tablets. Anti-histamines block the allergy reaction and could give false results. While steroids are less of a problem we prefer not to test while taking steroids by mouth. Anti-histamine and steroid creams are also potentially troublesome for the same reason. If you have any doubt about medications please check in advance. The following treatments are fine: asthma inhalers and nose sprays (no matter what is in them); eye or eardrops; the drugs Singulair or Accolate; antibiotics; tablets and liquid of drugs called Theophylline. Some simple paediatric preparations such as Dozol and Teedex contain antihistamine and cannot be used before any visit. Also, anti-depressants block allergy tests so I would advise against making an appointment if you are on anti-depressants.
If you wish to be seen for a fiberoptic naso-endoscopy check only and not allergy testing, you can continue to take your regular medications. No medications will interfere with the outcome.

If in doubt, please check in advance. Otherwise it could be a wasted journey.

When are blood tests used?
An allergy blood test is used when:
The patient is taking a medicine that can interfere with skin testing, but cannot be stopped for a few days
The patient suffers from a severe skin condition such as eczema
Testing with a strong allergen might cause an extra large positive reaction

How long does it take to get blood test results?
Because the blood sample must be sent to a lab for testing, it takes many days to get the results.

Which test method is best?
Skin tests give fast accurate results. They usually cost less than allergy blood tests.

What are the Pros and Cons of Skin Prick Test?

• Young children do not like skin prick testing
• Some medicines can interfere with the tests
• Some people with dark skin it may be hard to read the tests
• The skill of the tester may affect the results

What about Blood Testing?
Helpful because they involve a single needle prick.
Medicine does not interfere with the results.
It can take a long time to get the results, depending on workload at hospital lab.
Blood testing (called a RAST test) costs considerably more. At present a batch of (say) 20 separate allergens tested using the RAST method will cost about 660. However cost is not the main factor in deciding which is the most appropriate for your needs and RAST testing may be advised in certain situations. The test results alone do not diagnose allergies. All test results, from either type of test, must be interpreted together with the medical history.

Are there risks or side effects from allergy testing?
Any medical test involves some risk. The risk with allergy skin tests is that allergy symptoms might occur during the test. The most common symptoms are itching and swelling of the skin where the tests are. In extremely rare cases a more serious reaction can occur. The risk with allergy blood tests is pain or bleeding at the needle mark and fainting (due to a fear of needles and nothing to do with the test).

What does allergy testing find?
Allergy tests help find allergies to pollen, moulds, dust mites, animal dander, insect stings and foods.

Please note we DO NOT test for insect stings in Slievemore Allergy Facility and recommend the facility in Blackrock Clinic (Dr Bruce Mitchell) if you wish to have this checked