Treatments for post-inflammatory hyperpigmentation

Have you ever noticed dark spots or red patches that linger after your skin has healed? These marks are called post-inflammatory hyperpigmentation (PIH). PIH is a common skin issue that can be caused by acne, eczema, a small injury, or sun exposure.

While these dark marks can be frustrating, the good news is that you don’t have to live with them forever. This article explains how to treat post-inflammatory hyperpigmentation and lists the products you can learn more about today.

What is post-inflammatory hyperpigmentation?

First, let’s talk about what PIH is—and what it isn’t.

When the skin experiences an injury or irritation, it can trigger an overproduction of melanin, the pigment largely responsible for skin colour (1). This is a normal part of healing. However, it can cause dark marks that stay after the blemish has healed. These marks are called post-inflammatory hyperpigmentation, or PIH for short. PIH is more common in people with darker skin tones but can affect all skin tones and types (3).

PIH presents differently depending on the colour of your skin. On darker skin, it may look like brown or black marks that last longer. Lighter skin tones might show red or pink spots that fade faster.

Many people confuse post-inflammatory hyperpigmentation with acne scarring, as both can be left behind after breakouts. However, they are different skin conditions and require different treatments.

What is the best treatment for post-inflammatory hyperpigmentation?

Two powerful active ingredients stand out when it comes to post-inflammatory hyperpigmentation treatment: azelaic acid and adapalene.

Both products reduce discolouration and tackle the root causes of acne. They are ideal for those whose post-inflammatory hyperpigmentation comes from breakouts.

• Azelaic acid: A natural substance that slows down melanin production, which helps fade dark spots over time. It also fights bacteria that cause breakouts (4). It is known for its gentleness and anti-inflammatory properties, making it suitable for sensitive skin.
• Adapalene: A topical retinoid that blocks melanin production and helps skin cells turn over. This process sheds dead skin and encourages new skin growth. This reduces the appearance of dark spots and treats acne, leading to brighter, clearer skin (5).

Adapalene is available in the UK only with a prescription. It is sold under brand names like Differin. You can find it as an acne cream or gel. Products containing low concentrations of the active ingredient azelaic acid are available over the counter. But for treating P.I.H., stronger, prescription-only formulas are recommended, like Skinoren 20% cream and Finacea 15% gel.

After cleansing, all these treatments can be applied to the affected area (not individual spots or marks). Adapalene should generally be applied before bed, whereas azelaic acid can be applied twice daily, in the morning and at night (6). With continued use, skin pigmentation should fade.

Once the dark spots have faded, you can continue to use these products as part of your long-term skincare routine. Some people reduce their application to two to three times a week, which helps to keep skin clear and prevent future breakouts.

Azelaic acid vs adapelene: which is better?

Azelaic acid and adapalene offer similar benefits. However, azelaic acid, especially lower-concentration products like Finacea gel, may be better for sensitive skin. You may initially notice mild dryness or itching, but its gentle formula is generally well-tolerated (7).

Adapalene is stronger and more likely to cause dryness, peeling, and a burning sensation on application (8). These effects usually go away as the skin gets used to the treatment. However, people with sensitive skin may prefer azelaic acid.

You cannot use adapalene or other retinoids if you are pregnant (9), which is something for women to consider.

If you still can’t decide, why not try both? These products can safely be used together as a treatment for hyperpigmentation. Using one in the morning and the other in the evening helps your skin get the benefits of both ingredients. This routine also reduces irritation.

Tips for applying post-inflammatory hyperpigmentation cream

Adapalene and azelaic acid can cause dryness, redness, and irritation, but there are ways to minimise these unwanted side effects:

• Start by applying less often—perhaps every other day—and gradually increase as your skin gets used to treatment. If you experience irritation, reduce how often you apply your cream or gel until your skin adjusts.
• After using the post-inflammatory hyperpigmentation cream, let it soak into your skin. Then, apply a thin layer of non-comedogenic moisturiser. This type of moisturiser does not clog pores. It will help soothe and calm the area where you applied the cream.
• Be careful when using other active ingredients, like retinoids or exfoliants, in your skincare routine. They can cause more irritation. It's best to introduce new products gradually and consult a dermatologist if unsure.

Adapalene can also increase sun sensitivity (10), so it's important to apply a broad-spectrum sunscreen of at least SPF 30 every morning—though it should be part of your skincare routine as standard. If you have darker skin that is prone to hyperpigmentation, use sunscreens with iron oxide. These sunscreens offer extra protection and can help reduce hyperpigmentation from sun exposure (11).

What other hyperpigmentation treatment options are available?

While azelaic acid and adapalene are excellent first-line treatments for post inflammatory hyperpigmentation, there are other options:

• Tretinoin: Another retinoid, tretinoin, is similar to adapalene but may be slightly stronger. It helps skin cells turn over, fades dark spots, and clears acne better. However, it can irritate sensitive skin more (12).
• Chemical Peels: These treatments exfoliate the skin and can significantly reduce the appearance of dark spots (13). Chemical peels vary in strength and should always be performed by a qualified professional, as they can cause PIH on some skin types (14).
• Laser Therapy: Some laser treatments effectively break down melanin deposits (15). Always talk to a dermatologist to find the best treatment for your skin type. Chemical peels and laser therapy can cause PIH if not done correctly (14).
• Microneedling: This technique involves creating tiny micro-injuries in the skin to stimulate collagen production and improve overall skin texture. Microneedling can also enhance the absorption of topical treatments, reducing acne and skin pigmentation (16).

Hyperpigmentation treatment vs acne scar treatment

Acne is one of the most common causes of PIH, and many people confuse acne scarring with hyperpigmentation. It's important to know the difference between the two:

• Post inflammatory hyperpigmentation caused by acne refers to the red marks left by spots. It does not alter the skin's texture—these darker patches will remain flat and smooth to touch. Over time, the red marks fade as the skin heals.
• Acne scarring affects the skin’s structure and texture. Some acne scars, like ice pick, box, rolling, and atrophic scars, look like indentations.

Other types, such as keloid and hypertrophic scars, create raised bumps from scar tissue (17).

Correctly identifying your skin condition is key, as P.I.H. and acne scar treatments differ. Topical retinoids, such as adapalene, can treat mild acne scars and skin pigmentation (18) and help fight acne.

However, microdermabrasion or laser resurfacing is often necessary for severe scarring (19). Options for keloid scars may include steroid injections, topical steroids, or laser resurfacing (20).

Treating acne is always the priority before addressing any scarring or skin pigmentation concerns. Our pharmacy offers a range of acne treatments for anyone dealing with active breakouts.

Start your post-inflammatory hyperpigmentation treatment

Post inflammatory hyperpigmentation doesn’t have to be a permanent part of your life. Treatments like azelaic acid and adapalene can help reduce dark spots. They also keep your skin clear of future breakouts.

These treatments are available with a prescription from our independent online doctors, who provide remote consultations and deliver your skincare to your door. If you're ready to take control and tackle those pesky dark spots, explore our selection of Skinoren, Finacea, Differin Cream, and Differin Gel to start your journey towards a clearer complexion.

References

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