How to perform a patch test

We strongly recommend always performing a patch test before using any new skin care product of any brand, for anyone with known allergies, with sensitive skin or for anyone who has previously experienced a reaction to a skin care product.

This procedure helps determine if one may have allergic sensitivity to a product or ingredient. 

First apply the product on the inside of the wrist or elbow and wait 24 hours to observe any skin reactions or irritations.
 If the skin does not present any abnormalities following the first application on the inside of the elbow, then the product may be applied on the neck. Once again, it is best to keep the product on the skin for a minimum of 24 hours and evaluate how the skin reacts to it.

Apply the new product on the neck skin once a day, for three days in a row.

After 3 days of applications on the neck, let 3 days go by without any applications.  Resume to application of new product on the neck on the fourth day.  If there are no reactions after 24 hours, it is highly unlikely that the product would cause a reaction on facial skin.