As a board-certified dermatologist practicing in my 3 private offices in Manhattan, NY, I see many patients of color, and one of the most frequently asked questions is “what is a good treatment for my post acne scarring?” or “what is a great at home cream that I can use to treat my skin discoloration?” Skin discoloration is one of the most common reasons why people of color seek the care of a dermatologist. Also, skin discoloration can take a huge psychological toll on people of color because the condition is usually more severe and visible in darker skin.
First, let us define some terms. Post inflammatory hyperpigmentation or PIH is a common skin condition caused by excess melanin production and manifests as dark discoloration that occurs after skin inflammation e.g., in acne or after an injury e.g., a cut or wound. PIH is different from acne scars which are skin depressions or divots resulting from acne.
In 2000, the EU banned hydroquinone in concentrations above 1% because studies in mice showed the ingredient to be carcinogenic and some preparations were found to contain trace amounts of mercury. There is some controversy whether skin absorption level by humans has the same effect.
Tyrosinase is an enzyme present in melanocytes, the cells that produce melanin. Melanin must be transferred from melanocytes to keratinocytes, the skin cells.
Skin lightening active ingredients work by
- Inhibiting the enzyme tyrosinase
- Impairing melanin transfer from melanocytes to keratinocytes
- Or in the case of hydroquinone, in addition to inhibiting tyrosinase, they can also kill the melanocytes (cytotoxicity).
Unlike other skin lightening agents such as kojic acid, arbutin, mulberry extract that work by inhibiting tyrosinase, hydroquinone also kills melanocytes, the cells that make melanin.
7 non-hydroquinone alternatives to treat post inflammatory hyperpigmentation
Also know as nicotinamide, it is the active form of niacin (vitamin B3). It interferes with the interaction between keratinocytes (skin cells) and melanocytes (melanin forming cells) and it also modulates the protease-activated receptor (PAR-2) that is involved in the transfer of melanosomes (melanin carriers) from melanocytes to surrounding keratinocytes.
Note: It doesn’t stop the production of melanin, it stops the transfer of melanin to skin cells. Great for sensitive and irritated skin
2. Lactic acid
If you have sensitive skin or you are just looking for something mild, a skin lightening product containing lactic acid is great. Lactic acid is an alpha hydroxy acid and a great humectant that draws water into the skin. It also reduces skin discoloration.
Arbutin is a naturally occurring ingredient consisting of a molecule of hydroquinone bound to glucose. In the skin, Arbutin is slowly broken down into hydroquinone and glucose in a controlled manner. It is derived from the dried leaves of bearberry, cranberry, blueberry and pear plants. It is thought to act by reversibly slowing down the activity of tyrosinase rather than blocking the expression and production of tyrosinase.
It is a safer and effective alternative to hydroquinone because it is less cytotoxic to melanocytes compared to hydroquinone. It also has antioxidant properties.
4. Vitamin C
Vitamin C is a great antioxidant that reduces hyperpigmentation because it interacts with copper ions present at the active site of tyrosinase , thereby reducing the activity of the enzyme. Vitamin C, L ascorbic acid is unstable, resulting in low efficacy, and it is also very irritating. Therefore, I recommend Ascorbyl glucoside, because it is stable and safe for sensitive skin.
Ascobyl Glucoside is found in Adm Intuitive Brightening & Correcting Serum
5. Licorice root
This ingredient comes from the root of the licorice plant Glycyrrhiza glabra. Glycyrrhizin is responsible for the root’s sweet taste, as well as its antioxidant, anti-inflammatory, and antimicrobial properties while both liquiritin and licochalcone inhibit tyrosinase and treat hyperpigmentation.
Note: Licorice root extract is great for sensitive and irritated skin. In addition to helping with dark spots, licorice can be soothing and help even out your skin tone
6. Azelaic acid
Azelaic acid is a naturally occurring dicarboxylic acid derived from rye, wheat, and barley that it inhibits tyrosinase and treats hyperpigmentation. This ingredient is also FDA-approved to treat mild to moderate rosacea and acne. It can be used in pregnancy.
7. Mulberry extract
Mulberry extract is derived from the plant Morus alba. Mulberry extract has been proven to help in skin lightening through anti-tyrosinase activity which produces skin lightening. Mulberry extract has been shown to be as effective as kojic acid. So if your skin is irritated by Kojic acid or you are unable to tolerate Kojic acid, Mulberry extract might be a great alternative.
Green tea extract acts on various biochemical pathways hence causing anti-inflammatory, anti-oxidant and anti-carcinogenic effects.
Kojic acid is produced by certain fungi and it is a by-product of rice fermentation. It reduces hyperpigmentation by inhibiting the production of free tyrosinase and is also a potent antioxidant. In addition to skin lightening, Kojic acid has many uses in the skin such as antimicrobial, antifungal, anti-inflammatory. It is safe to use in pregnancy
Note: it can be irritating so start with 1% Kojic acid. Remember it is an acid, so start low and go slow with this ingredient