By: Nikki D. Hill, MD, Board-Certified Dermatologist and Hair Loss Specialist
Hyperpigmentation, or darkening of the skin, is a major concern for patients. There are different reasons to develop hyperpigmentation. In this article we will discuss postinflammatory hyperpigmentation (PIH) which is the most common form.
PIH occurs as a result of inflammation or injury to the skin. Any person who has the ability to tan has the ability to develop PIH. If there is prolonged redness or obvious damage to the skin, when it heals, the injury site will produce more melanin (read about melanin) which results in PIH. There is an initial fading period of the dark spot/PIH over the next 3 months; however, complete resolution is often not achieved naturally.
Prevention of PIH is always easier than treatment. I counsel patients to try to reduce as much trauma and irritation to the skin as possible. Acne bumps, picking lesions, leaving chemicals on the skin overnight (benzoyl peroxide, toothpaste, witch hazel, alcohol) often lead to dark spots. Also if there are any reasons for inflammation such as acne, ingrown hairs, cysts, or keloids try to treat those conditions first so you aren’t chasing after new PIH lesions that may occur.
When patients present with PIH I first find out the reason for the PIH and develop a timeline of when the PIH started. Pigment changes that developed years ago are more difficult to treat. More recent PIH has a better chance of completely fading with the help of lifestyle changes and medications. Below I have listed common treatments for PIH by commercial products, prescriptions and procedures.
Over the Counter
Suncreen is very important to prevent further darkening of PIH lesions. I tell patients to protect in the morning (with sunscreen) and treat at night. Applying a sunscreen with an SPF30 every morning is necessary. Imagine every time you walk outside the skin naturally tans to a small degree. If the PIH areas get the same amount of sunlight, they too will tan and remain darker for a longer duration of time. There are many brands of sunscreens that are mild and oil-free . Avoid sunscreens containing pure titanium dioxide or zinc oxide if you have a richer skin tone because they will look white or greyish blue on your skin. If you have particularly sensitive skin, try Cetaphil, Cerave, or specifically Vanicream which is a hypoallergenic hygienic product line (can be purchased at Walgreens).
Hydroquinone (HQ 2% is the ingredient in Ambi fading cream) is used as a night time spot treatment. It is not recommended as a full area treatment because it not only fades PIH but it will also fade normal skin color. Consequently, if you treat outside the PIH spot, you will notice a halo of light colored skin between the PIH and your normal skin tone. If this occurs, a tincture of time will allow the normal skin tone to create melanin and even out. HQ can be very effective for some individuals and knowing when to stop using the medication is important. A potential side effect with long-term use of HQ is the development of ochronosis, a permanent deep blue-black color of the treated skin. I counsel patients to use this medication for a few months and then take a break to reduce the risk of developing ochronosis.
Retinol is a more selective with removing melanin from the dark spots only and leaving the normal skin tone unaffected. Retinol also has the added benefits of stimulating collagen in the skin to help fade out fine lines, reducing oil production, exfoliating the skin to help with skin glow, and removing whiteheads and blackheads. Retinol should be part of a night time regimen. Due to the exfoliating nature of retinol, external elements may irritate the skin a little easier. Sunscreen should be worn daily to prevent sun burn and rough exfoliators should be avoided while using this product.
Kojic Acid is found in brightening creams and helps with fading PIH.
Vitamin C and Copper work by reducing inflammation so the skin is less susceptible to produce PIH. Glycolic acid can be found in wipes and facial cleansers and acts to fade out dark spots.
Natural ingredients include soy, niacinamide, and sour milk, and lignen help fade out PIH by limiting the amount of melanin being transferred to skin cells.
Retinoids are the stronger version of retinols. Retinoids can produce more intense exfoliation, collagen stimulation, and fading of PIH. Sunscreen should be used with this product.
Hydroquinone 4% and stronger are prescription strength fading formulations. Strict sun protection is important.
Compounded medications that may include retinoids, hydroquinones, and topical steroids can help fade PIH quicker. Caution should be noted with the use of topical steroids to treat PIH. Side effects of steroids include lightening of the skin but also include development of stretch marks and thinning of the skin. Needless to say you don’t want to use creams with steroids for a long duration of time.
Chemical peels are used for superficial and deep exfoliation to remove stubborn PIH. There are different strengths of chemical peels depending on the type and the depth of the pigment being treated. I advocate seeing a dermatologist for your peels so if you have complications you are in a location to treat such complications.
Lasers can reduce the intensity of deeper PIH but require specific lasers to treat skin of color to reduce risk of complications such as burns, pigment loss, and worsening PIH.
It is important to mention that using multiple chemicals at once can lead to irritation and possible chemical burns on the skin. You should always discuss your facial regimen with a physician to ensure you are not using a combination of chemicals that may lead to aesthetically upsetting complications. And remember, protect in the morning with sunscreen and treat at night.
Nikki D. Hill, MD
Board-Certified Dermatologist and Hair Loss Specialist
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