What Is Patch Testing?

Patch testing is a useful tool in dermatology used to evaluate the potential triggers of Allergic Contact Dermatitis, a common rash that occurs when your skin comes into contact with certain substances. The skin patch test is used to help identify allergens within your environment that may be causing skin irritation or inflammation leading to the resultant rash. It is important to note that patch testing is not the same as prick testing and cannot be used to determine food allergies or respiratory allergies. Here at ReJUVA Dermatology and Skin Cancer Center, we offer one of the most comprehensive series of patch testing to better identify the allergens.

What Is Allergic Contact Dermatitis?

Allergic Contact Dermatitis (ACD) is a type of skin rash that occurs when you touch or come in close contact with certain substances or agents that your skin has been previously sensitized to. This rash is an inflammatory condition caused by Type 4 cell-mediated hypersensitivity reaction. Once an allergy to a specific substance develops, patients will develop a flare-up any time they come in contact with that specific allergen. This may cause prolonged dermatitis leading to patient frustration. Eruptions resolve when the cause is identified and avoided which is why a skin patch test is extremely important in the diagnosis and treatment of this condition.

Multiple new studies are validating the finding that many patients with chronic dermatitis have an allergic contact dermatitis that its cause can be identified and prevented using patch testing.

This rash can present as itchy, red to purple, scaly, sore, oozing, or crusted bumpy or blister-like lesions on the skin. Chronic ACD caused by recurrent or prolonged contact with allergens may present as lichenified or thickened skin with fissuring and scale.

Types of allergens can vary greatly depending on geographic location, personal habits, occupation, and hobbies. Common culprits include plants, hair dyes, skin care products, jewelry containing certain metals, medications including antibiotics, preservatives, textile chemicals, and fragrances. Sometimes patients are exposed to allergens for years before developing a hypersensitivity reaction. Morphology and location of the rash help clue providers into what may be causing this type of dermatitis.

Call us at
(941) 529-0070 Book Your
Appointment Now

How Does Allergy Patch Testing Work?

Patch testing is simple, reliable, safe, and yields important information in the diagnosis of Allergic Contact Dermatitis. The test is performed by placing an adhesive panel on the patient’s back that contains chambers loaded with common allergens. Our allergy patch testing panel is very comprehensive and contains a wide array of 80 common allergens frequently encountered by North American patients including various metals, fragrances, preservatives, medications, and dyes. Once applied, the patch test remains in place for two days (48 hours). After 48 hours, patients will return to the office to have the panel removed and the results read 20 minutes after removal. During this time, your provider will examine the skin on your back for any reactions to the labeled allergens. Patients will return to the office for a follow-up appointment 1-2 days later for a re-reading of the patch test results. Most reactions occur within this period, however, some delayed type reactions are also possible and should be reported to your provider. Results from an allergy patch test in conjunction with the history of the rash and physical exam findings help guide the therapeutic approach. It is important to note that patch testing will not test for respiratory allergens.

Call us at
(941) 529-0070 Book Your
Appointment Now

Who Is a Good Candidate?

A skin patch test should be considered in patients who are diagnosed with unspecified dermatitis or who have a history of chronic rashes like Eczema. Many patients who have been previously diagnosed with Eczema or Atopic Dermatitis may have a component of ACD that can contribute to recurrent rash outbreaks. Without proper diagnostic workup, some patients struggle with Allergic Contact Dermatitis for years.

Some patients with certain occupations are at higher risk of developing allergic contact dermatitis including hair stylists, florists, healthcare professionals, construction workers, mechanics, and food handlers among others.

Based on historical elements of your rash and its appearance during physical examination, your provider will let you know if you are an appropriate candidate for this diagnostic test.

Call us at
(941) 529-0070 Book Your
Appointment Now

What Can I Expect During a Skin Patch Test?

You may experience mild irritation, redness, swelling, burning, or itching at the test site – this is a normal anticipated response to any allergens your skin is reactive to. Patients are advised not to scratch the patch testing sites, as this can cause further irritation to the skin and may also alter the test results. While the skin patch test is in place, patients are advised to minimize water exposure including bathing or showering, or avoid the use of steroids or antihistamines.

What Are My Treatment Options?

Patch testing helps identify allergens that patients might be allergic to and can avoid to prevent the recurrence of their dermatitis. Resources are available to help patients generate a personalized safe list of products. Eliminating contact with the specific offending agent is a first-line therapy in the treatment of ACD. Topical steroid creams/ointments or oral steroid dose packs in combination with oral antihistamines can help control symptoms of inflammation and itchiness. Additionally, patients should wash their hands and skin immediately after coming in contact with a known allergen.

Patch Testing

What Is Patch Testing?

What Is Allergic Contact Dermatitis?

How Does Allergy Patch Testing Work?

Who Is a Good Candidate?

What Can I Expect During a Skin Patch Test?

What Are My Treatment Options?

Contact Our Venice, FL Office for Allergy Patch Testing