Postinflammatory hyperpigmentation PIH
What Causes Postinflammatory Hyperpigmentation?
The initiating inflammatory process causes melanocytes (pigment producing cells) to produce excess melanin. This triggers off oxidation of a variety of chemicals within the skin to stimulate melanocytes. The excess melanin are then deposited into normal skin cells. The deposition of melanin may involve the epidermal (superficial) layer, dermal (deep) layer or epidermo-dermal layers (mixed) of the skin. Inflammatory that is prolonged, severe or relapsing will increase the risk of postinflammaotory hyperpigmentation.
Who Gets Postinflammatory Hyperpigmentation
Although postinflammatory hyperpigmentation PIH can occur in just about anyone, it is more common in individuals with darker skin. It can occur at any age, any body part and affects both men and women equally.
PIH is also more common in individuals with sun-induced skin conditions and if on certain medications e.g. tetracyclines, anti-malarials, bleomycin.
What Does PIH Look Like?
Patches of light to dark brown colour will be observed at the site of existing or previous injury or inflammation. Dark gray to bluish discolouration suggests a deeper dermal involvement. Postinflammatory hyperpigmentation darkens after sun exposure and can persists for months to years.
How Is Postinflammatory Hyperpigmentation Diagnosed?
Most cases of postinflammatory hyperpigmentation can be diagnosed through a history and examination of the affected area. On occasion, a skin biopsy may be needed in cases of uncertainty.
Postinflammatoy Hyperpigmentation Treatment
Any existing inflammation or infection must be dealt with promptly and effectively. For example, acne is a common cause of postinflammatory hyperpigmentation. Treating acne early and aggressively to reduce the inflammatory component is necessary to treat the cause and effect of the disease.
A regular use of sunscreen, protective clothing and sun avoidance behaviours are essential in Singapore. Steps should be taken to avoid picking at your skin to reduce further skin irritation and inflammation.
Topical & Chemical Peel Treatments for PIH
Topical lightening treatments for PIH work by blocking further pigments, fading excess pigments and increasing skin turnover. Topical therapies are more successful at treating epidermal PIH rather than deeper dermal PIH.
Topical & chemical postinfammatory hyperpigmentation treatment options include:
- Azelaic acid
- Vitamin C
- Triple therapy (Hydroquinone + Retinoid + Steroid)
- Chemical peels (glycolic, salicylic acid)
Laser Treatment Postinflammatory Hyperpigmentation
Laser treatment of postinflammatory hyperpigmentation can be considered in cases that are long-standing, PIH refractory to topical treatments or dermal PIH involvement. Pigment specific lasers such as the Q-switched and Pico-second lasers work by breaking down melanin into smaller fragments which are subsequently cleared by your body. Pico-second lasers causes less collateral skin damage and are safer in darker skin types. However, laser treatments for PIH must be done cautiously, high energy laser treatments may potentially darken your PIH.
As each case is different, a consultation with your doctor to discuss the best postinflammatory hyperpigmentation treatment option that is unique for your skin type and condition is essential.
Postinflammatory hyperpigmentation is not an easy condition to manage. The first step would be to address any existing inflammation, infection or injury to the skin.
While some cases of PIH do resolve by themselves without treatment, many cases of PIH can persists over months to years causing emotional distress, affecting self-esteem and confidence.
While lasers are effective for many pigmentation conditions such as freckles, lentigenes and Nevus of Ota, it is considered second-line therapy for PIH. Laser treatment has to be performed cautiously as it may sometimes darken the pigmentation further.
Any existing inflammation, infection or injury to the skin makes you unsuitable for laser treatment. The underlying cause of your PIH should be managed and treated before considering any laser treatment.
This depends on the severity of PIH, duration and how deep the melanin extends below your skin. Multiple treatments (4-10 sessions) may be required to see an improvement in your PIH
Postinflammatory hyperpigmentation treatment can be a long and challenging process. Even with treatment, it may take at least 6-12 months or even longer to see an improvement.
PIH is due to excess melanin that is deposited within the skin. Atrophic Acne scars are due to a loss of collagen within the dermal layer of the skin. Acne scars are classified as ice pick, rolling and boxcar according to their appearance. As a result, the treatment for PIH and acne scarring is different.
- Management of post-inflammatory hyperpigmentation in skin of color: A short review. J Cosmet Dermatol. 2022; 21: 1837– 1840. doi:10.1111/jocd.14916 , , .
- Elbuluk, N., Grimes, P., Chien, A. et al. The Pathogenesis and Management of Acne-Induced Post-inflammatory Hyperpigmentation. Am J Clin Dermatol 22, 829–836 (2021).
- Feng, J. and Huang, L. (2022), Treatment of permanent post-inflammatory hyperpigmentation with medium-fluence medium-spot-size setting in Q-switched Nd: YAG 1064 nm laser: A novel treatment parameters setting strategy. J Cosmet Dermatol, 21: 1300-1302.