What is patch testing?


Patch Testing: The Nuts and Bolts

Have you ever had a chronic rash that you suspect may be caused by a product or material you are using? If so, you may be suffering from contact dermatitis. This common condition occurs when your skin comes in contact with an irritant or allergen that you are sensitized to, triggering an inflammatory rash. To learn more about contact dermaittis, click here (link to contact derm article).

A “patch test” or “patch testing” refers to a simple diagnostic procedure that is used to identify potential substances that may be causing your allergic contact dermatitis and is considered the test of choice by both Allergists and Dermatologists in diagnosing this condition. By identifying the specific source or sources that are causing your allergic reaction, you will be able to practice avoidance in the future. Below, we’ll go into detail about what a patch test is, why it’s important, how the process works, and what you can expect both during and after the procedure. Let’s dive in!


What is patch testing?

Patch testing involves the strategic placement of multiple potential allergens on the skin. These allergens include many common ingredients found in a variety of personal care and other household products. The patch test is left in place for 2 days, after which time it is removed. The test site will be observed at both the time of patch test removal and the day after removal for any positive reactions. If you are diagnosed with allergic contact dermatitis, the next step will be to avoid any products that contain the substances you are allergic to.


How is patch testing typically performed in a doctor’s office? 

Traditionally, patch testing has only been available through an Allergy or Dermatology specialist and will involve several in-person visits. Initially, there is a consultation visit at which your symptoms will be discussed. If patch testing is recommended, you will then be scheduled for one patch test “placement” visit and two patch test “read” visits to observe for any allergic reactions. In total, most people will need to be seen in the office 4 separate times to complete the full patch testing process.

The three separate “placement” and “read” visits are usually completed over a 4-day span, during clinic hours.  During the patch test “placement” visit, the patches are attached to your skin using an adhesive-backed bandage. Each “patch” contains 10 chambers to hold 10 individual allergens. The number of patches used is dependent on the number of allergens tested for. 

Once the patches are affixed to your skin, you will leave the office with instructions for two follow-up “read” visits scheduled at both 48 hours and 72 hours after placement. During this procedure, you will need to refrain from showering or participating in activities that cause excessive sweating (exercise, working in the heat, etc). 

At your first “read” visit  (48 hours), the patch is removed and a preliminary interpretation of the results is conducted. The patch is not reapplied at this time, but you will still need to keep the area that is being tested dry. 

At your second “read” visit (72 hours), a final interpretation is done and the results are discussed with you.  A positive patch test is typically based on the amount of skin reaction observed and is graded as a 3+ (very positive), 2+ (positive), 1+ (weakly positive), or IR (irritant reaction). You may find that you have allergic reactions to several of the allergens that were placed. When discussing your results, the doctor will provide you with a list of the substances that were tested. They will also provide information on what allergens you reacted to and counseling on how to best avoid them.

Side effects you may experience during or after patch testing include some mild to moderate redness or irritation at the test site due to a positive result (allergic skin reaction) or from the adhesive (irritant skin reaction). These symptoms will generally fade within hours to days of testing, but in some cases, can take longer to go away. A severe allergic reaction to patch testing is extremely rare and is never life-threatening.


What to expect after patch testing

Once your patch testing is complete, you may resume everyday activities. If there is any residual skin reaction, you should continue to monitor the area to ensure it resolves. If it is not improving within a few days, you will need to discuss treatment options with your healthcare provider.  In certain cases, an oral or topical steroid may be recommended to help alleviate your symptoms. 


How is Patchably Different as compared to in-office patch testing?

While patch testing is a valuable tool in determining the root cause of allergic contact dermatitis, many people choose not to pursue this testing for a variety of reasons, including:  

  • Lack of awareness that patch testing is possible or available
  • Lack of access to a specialist (Allergy or Dermatology) who performs patch testing
  • Prolonged wait times to see a specialist

There are also various obstacles people have with scheduling patch testing:

  • Limited availability for multiple in-office appointments
  • Inflexible home or work schedule to accommodate the visits, which may include out-of-town travel
  • Your lifestyle does not allow you to adhere to the requirements of testing
  • The long commute to the specialist’s office where patch testing is performed makes it undesirable to pursue this option

With Patchably, our goal is to help you get patch testing without all the hassle. We know that your time is valuable, and finding time in your busy life to make room for not 1 or 2, but 4 separate doctor visits can be overwhelming and needlessly complex. We make testing easy by sending the patch test to you instead of you coming to the patch test! 

With our patch testing kit, you will receive all of the materials you need to perform the EXACT SAME medically approved patch test done in person at your doctor’s office. However, instead of having to work out all of the details such as travel and scheduling, we make it so you can complete patch testing in 3 easy steps. All you need is a friend or family member that is willing to assist:

  1. Prepare and place your patch in the comfort of your own home at a time that works best for you.
  2. At the 48 hour mark, remove your patch, then take and upload your preliminary photos.
  3. At the 72 hour mark, take and upload your final photos. 

That’s it! The process is straightforward and we will be with you through every step to ensure you get the most accurate results. In addition to providing you with detailed instructions on how to prepare and apply the patch, we have a highly trained support team that can be reached by phone to help you through the process and address any questions or issues that may arise. 

Remember, unlike traditional patch testing, our patch can be applied anytime, anywhere, in less than 30 minutes!  

After your test is complete, you will be provided with a comprehensive list of all allergens tested along with detailed handouts for any positive results.

In addition, we provide you with complimentary access to the “Skin Safe” website and mobile app, as an additional resource to help you succeed in avoiding the allergens triggering your contact dermatitis.

Skin Safe, in collaboration with the Mayo Clinic, is a company that provides access to a comprehensive database of over 90,000 products and their ingredients. Rather than playing detective and having to individually review all of your own products, Skin Safe takes the guesswork out by telling you exactly what products should be avoided based on the allergic reactions identified during your patch test. In addition, they also provide an extensive list of products that are allergen free and safe for you to use. This will allow you to quickly search and compare products based on brand, category, ingredient list, or product rating.

In addition to providing detailed information about each product listed in its database, Skin Safe also offers helpful resources such as product recommendations, reviews from other users, and tips on how to reduce exposure to allergens. This database is an invaluable tool for those with contact dermatitis and allows them to easily identify products that are safe for their skin.


Should you get patch tested?

Patch testing is an important diagnostic procedure that can help individuals identify and treat contact dermatitis. If you are suffering from a rash and think you may be having an allergic reaction, patch testing will be able to help you more accurately determine what substances are causing your symptoms so you can avoid them. Patch testing can prevent the trial-and-error process of cycling through countless products or relying on treatments that only focus on the symptoms rather than the cause of your contact dermatitis. Patch testing can provide you with more targeted care while reducing exposure to additional irritants and side effects of unnecessary treatments at the same time.


In summary:

Patch testing is a safe and proven way to identify the cause of contact dermatitis. Although undergoing patch testing has traditionally been time-consuming and required much effort, this is no longer the case! With Patchably, you can say goodbye to multiple time-consuming in-office visits. Our at-home patch kits make the process quick, easy, and convenient, requiring no travel, no rearranging your schedule, and no time off of work. You can apply our patch test any time and any place as long as you have access to a cell phone and the internet to send us your photos. 

Remember, patch testing is generally well tolerated, with a low risk for severe allergic reactions. As I’m sure you’ll agree, the benefits of patch testing far outweigh any temporary discomfort, making it an indispensable tool in the diagnosis of contact dermatitis. With Patchably, you will get valuable insights into what might be triggering your allergic reaction to help your skin become clear again! Contact us today to purchase your Patchably at-home patch testing kit!

Get your allergy test kit today.