Allergy Testing
How do you test for allergies?
Prick skin testing is the most accurate and rapid way to diagnose allergies in individuals of all ages, and in general, is easily tolerated. We gently prick the skin on your forearm or back with a small disposable plastic device holding a trace amount of a solution containing the allergen to which you might be allergic. Those with significant allergies will develop a reaction similar to a mosquito bite at the testing site within 15 minutes. This is our clue as to what might be causing your problem.
Does allergy testing hurt?
In general, prick skin testing causes minimal or no discomfort, although individuals with extensive allergies may have a fair amount of itching at the testing sites, which can last for an hour or two.
Do you use needles?
In individuals with suspected allergies who show minimal or no relevant positive prick skin tests, or in those with allergies who are candidates for allergy injections, we may perform a second set of skin tests with needles by the intradermal technique. This method is more precise in identifying allergies than prick testing, and involves a small injection of the allergen into the skin on the upper arm, similar to a tuberculin (TB) skin test. As with prick skin testing, relevant reactions develop within 15 minutes, and resolve within a few hours.
Can medications that I’m taking interfere with allergy testing?
Some medications can (and usually do) interfere with allergy testing. If possible, and in order to avoid scheduling a second visit for allergy testing, we prefer that you discontinue all prescription and over the counter antihistamines at least 3-4 days prior to your visit. Some, but not all, medications for insomnia, anxiety, pain and depression can interfere with testing as well. Please call us if you are taking any of these medications for more specific advice. Most nasal sprays and asthma medications do not interfere with testing, and should be continued as usual.
Do you ever get blood tests?
Rarely, we will recommend that your allergies be assessed with blood tests. We do not draw blood in our office, but will refer you to an outside lab for this purpose.
Asthma Testing
How do you test for asthma?
Spirometry is the most accurate breathing test to measure asthma, and can be reliably performed in most adults and children 5 years of age and older. This involves taking a deep breath, and exhaling forcefully for several seconds into a tube that is connected to a computer. Because the results of spirometry are dependent on effort, we will ask you to perform several tests to ensure the results are accurate. Our nurses will help you if you’re not sure what to do.
In some circumstances, we may have you use a fast-acting asthma inhaler (or nebulizer) after you perform your first spirometry, and repeat the test 15-30 minutes afterward. The change (or lack of change) from the first test to the second often helps us to make important asthma management decisions.
Rarely, we may ask you to perform more extensive asthma testing by “challenging” you with either exercise or an inhaled substance called “methacholine.” We then perform spirometry at set intervals during or after the challenge, looking for a specific decline in lung function. If this occurs, we then give you a fast-acting inhaler to restore your normal lung function. Because this type of testing requires extra staffing, we only perform challenge tests on specific days and times.
Are there any side effects with asthma testing?
Other than occasionally becoming lightheaded, spirometry is well-tolerated. Viral respiratory illnesses (i.e. colds and flu) cannot be transmitted from equipment used in breathing tests.