Patch Testing Specialist

Advanced Allergy Associates

Cheryl Williams, M.D.

Allergy, Asthma, & Immunology Physician located in New Orleans, LA

Patch testing is one of the most advanced and effective ways to diagnose which contact allergens are causing your skin irritation. This is offered by Cheryl Williams, MD, at Advanced Allergy Associates and you receive your results within 48 hours of placement. Call the New Orleans, Louisiana, office today to schedule a consultation and see if patch testing is the right step in diagnosing your dermatitis.

Patch Testing Q & A

What is patch testing?

Patch testing is a useful diagnostic tool if you have contact dermatitis, an allergic skin reaction that occurs when you come in contact with a trigger substance, like latex or a specific chemical. More than 15,000 substances can cause contact dermatitis. 


Some causes of skin irritation are easy to narrow down as they result in a clear reaction that’s obvious to a trained allergist’s eye. In many cases, however, it’s difficult for Dr. Williams to determine the cause of your skin irritation without more information.


Dr. Williams may recommend patch testing if you suffer from itchy skin, regular redness, swelling, and rashes, or other unexplained skin irritation. When the cause of your dermatitis is suspected to be due to contact with a substance such as dye, nickel, fragrance, etc., patch testing helps with the diagnosis. 


How does patch testing work?

Dr. Williams places a small amount of suspected allergens on your skin, usually on your back, and covers each with a patch. You leave the area alone and avoid getting it wet or sweaty for the next 48 hours. Even if the patch feels itchy or irritated, it’s important that you not disturb the test site.


If you’re allergic to one of the dozens of allergens the patch test detects, you’ll develop a red, itchy, raised bump.

Which allergies does patch testing detect?


Dr. Williams customizes patch testing to your symptoms, suspected triggers, and health history. Some of the most common allergies tested for include:


  • Latex
  • Fragrances
  • Preservatives
  • Specific drugs
  • Metals


Prior to testing, Dr. Williams may ask you to maintain a journal documenting your symptoms and the activities that occurred at the time of your flare-up. This helps her narrow down possible causes to test for during the patch test.

What happens after patch testing?

If the test reveals a specific allergy, Dr. Williams develops a treatment plan to help you avoid the allergen and medication to use if symptoms do arise. 

Schedule your allergy patch test at Advanced Allergy Associates today. Call the office or use the online tool to request an appointment.