Patch tests a pain-free, reliable way for Elgin residents to identify irritants, causes of allergies

Patch tests a pain-free, reliable way for Elgin residents to identify irritants, causes of allergies

A skin test may have turned up false positive. You still suspect other allergies, despite a blood test. Inflammation may be so serious it prevents you from having a skin test, which may further irritate your flesh.

For these and other reasons, we may want to conduct a patch test. Generally, patch testing involves applying a tiny amount of the suspected culprit substance to your skin — via a waterproof, medical-grade adhesive. We will then check how your skin reacts to this small amount of potential allergen at intervals, usually 48 hours, 72 hours, and in some cases, additional testing may be done.

Considered a cornerstone of contact dermatitis diagnoses, the International Contact Dermatitis Research Group has established general guidelines, governing the resulting skin reaction post-patch test (should a reaction be noted), as follows:

  • Mild redness – reaction questionable
  • Red, slightly thick skin – probable yet weak reaction
  • Red, swollen skin and small blisters – strong, positive result
  • Intense redness, swelling and big blisters – extreme positive

In the case of suspected contact dermatitis, the distinction is made between irritant dermatitis and the far less common form of this skin inflammation – allergic.

If an irritant such as a cosmetic, solvent like kerosene, or detergent is to blame, reddened skin should improve once the patch is removed.

Some substances are trickier, and only cause allergic reactions should they be exposed to sunlight (usually ultraviolet rays are responsible).

In cases when, for instance, rashes are only observed in areas exposed to the sun (face, neck, back of hands, shoulders), photo-patch testing may be recommended. This type of patch testing is the same as the “standard” option — only two sets of the same substances are applied to your skin. One set is exposed to UV light; the other is not. Skin is later examined to see if the substance prompted a reaction in the area exposed to sunlight.

Dr. Noga Askenazi and the staff in Elgin offer patch tests to narrow down the reasons your skin may be behaving badly, so you can take the appropriate steps to avoid these substances and reduce your symptoms. Symptom-free is a call away at (847) 888-8802.

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Advanced Allergy & Asthma Associates

Dr. Noga Askenazi | Meredith Cirrincione

Dr. Noga Askenazi is a nationally recognized asthma and allergy specialist who is board certified in pediatric and adult allergy. Her areas of special interest are innovative treatment of rashes, sinusitis, food allergies, asthma and immune disorders. She was past President of the ISAAI (Illinois Society of Allergy, Asthma, & Immunology), works on state and national committees for advancement of the allergy field and is a consultant for Advocate, Ascension Health, Northwestern amongst other health care systems. Her joy is helping patients reach their goals after together determining best treatments. Her staff and patients are a chosen family, and she invests in their happiness. She enjoys gardening, biking and cooking to good music.


Meredith Cirrincione is a board certified Physician Assistant and specializes in treating allergies, with a focus on asthma, rashes, environmental allergies, chemical and food allergies. She holds a Masters in Physician Assistant Studies from The Chicago Medical School - Rosalind Franklin University of Health Sciences. She is a Fellow member of the American Academy of Physician Assistants, the Illinois Academy of Physician Assistants, and the Association of PAs in Allergy, Asthma and Immunology. She likes to approach things holistically. She is a strong patient advocate and adored by her patients. She enjoys singing, reading, cooking, and the great outdoors.