PAR-2 Blockers To Lighten Skin and Even Skin Tone

Protease-activated receptor 2 (PAR-2) is a receptor in the epidermis of the skin that can be blocked to lighten skin color. Niacinamide is an example of a PAR-2 inhibitor. Blocking this receptor can also help prevent melasma and hyperpigmentation from coming back.

Adding PAR-2 blockers to your skin-lightening regimen is one way to lighten skin faster. We recommend using several types of skin lighteners in your skin care routine to lighten dark spots on the skin. PAR-2 receptor blockers can be used with retinoids and tyrosinase inhibitors and other skin lightening ingredients.

Treating uneven skin tone such as melasma and dark spots is challenging because skin lightening ingredients take 8-16 weeks to work. There is no way to lighten skin overnight, but there are tips to make skin lightening treatments work faster and better such as using skin lightening ingredients from several different categories in your skin care routine. PAR-2 blockers is one of those categories.

To understand how PAR-2 blockers work, you need to now how the skin pigment melanin gets into the skin cells called keratinocytes.

Skin pigment, known as melanin, is made in the melanocyte cell and packaged in melanosomes for delivery to skin cells. One melanocyte provides melanin to 35 or more skin cells in the epidermis. Melanocytes move around in the epidermis and dermis, but for this discussion, we are going to visualize melanocytes located in the bottom of the epidermis of the skin forming an Epidermal Melanin Unit. Each melanocyte looks like an octopus and has long arms that extend between skin cells in the epidermis called keratinocytes.

The skin pigment melanin, packaged in melanosomes, travels up the arms of the melanocytes and into the 36 + attached keratinocytes. This causes the skin color to darken.

At the connection points between the melanocyte and the keratinocytes, there is a receptor that functions like a locked doorway. This doorway is called the PAR-2 receptor. In order for melanosomes filled with melanin to travel from the melanocyte into the keratinocyte, the PAR-2 doorway must be open. Skin lightening ingredients that block the PAR-2 receptor prevent this movement of the melanosomes, preventing skin pigmentation.¹

Skincare ingredients can be used to block the PAR-2 receptor. These function as locks on the PAR-2 doorway which prevent movement of melanin into skin cells. Using a PAR-2 blocking skincare ingredient will prevent skin pigmentation. PAR-2 blockers do not lighten dark skin fast but prevent further pigmentation so it can take over 30 days to see a difference in skin color with skin lighteners. PAR-2 blocking ingredients should be used in combination with tyrosinase inhibitors which prevent the production of melanin, and exfoliants which help desquamate away old skin cells so they can be replaced with newer less pigmented skin cells. Of course, sun protection must be used to prevent the formation of new melanin.

The most commonly used PAR-2 blocking cosmeceutical ingredient is niacinamide. Niacinamide has many important functions such as decreasing inflammation, increasing cell energy to help cellular repair processes, and blocking PAR-2. Combine niacinamide in a skin lightening skincare routine with tyrosinase inhibitors, a retinoid, a tinted sunscreen, and exfoliants such as hydroxyacid cleansers and retinoids is the best way to remove dark spots on the skin. Other PAR-2 blockers such as activated soy found in Aveeno products are used to lighten skin. New PAR-2 blockers are being developed to be used in skin lightening products. Stay tuned on social media @SkinTypeSolutions to learn when new PAR-2 blockers come on the market.

There are not a lot of ingredients that block PAR-2. Here is a list of PAR-2 blocking skin care ingredients:

Niacinamide

Active Soy 

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