What Is PIH?
Post inflammatory pigmentation is temporary pigmentation that follows an injury. PIH has a higher prevalence in darker skin types (Fitzpatrik Scale: type 4-6). In darker skin types, the pigmentation stay for longer periods and is more intense due to the high melanin content in their skin types. Postinflammatory pigmentation is also called MELANOSIS.
Causes of PIH
Pigmentation happens due to the damage of the epidermis and/or dermis with deposition of melanin within the keratinocytes (skin cells) and/or dermis.
Inflammation in the epidermis stimulates melanocytes to increase melanin synthesis and to transfer the pigment to surrounding skin cells.
Various causes:
- Sun damage
- Injury/Direct trauma to the affected area
- Acne scarring
- Eczema scars
- Incorrect use of laser treatments, chemical peels
Clinical Features of PIH
Post-inflammatory hyperpigmentation patches are located at the site of the original disease after it has healed. The lesions range from light brown to black in colour. The patches may become darker if exposed to sunlight (UV Rays)
PIH from inflammed cyst 
Pigmentation on hands from eczema scar 
Pigmentation from friction
How Is PIH Diagnosed?
Post-inflammatory hyperpigmentation is diagnosed by taking a detailed history from a patient and examining the skin by an experienced doctor. These changes in the skin alter the skin’s colour to a darker shade (grey-purple-brown).
In rare circumstances a skin biopsy is performed to identify the changes and likely causes of the skin discolouration.
What Is The Treatment for PIH?
- Q-Switch NDYAG Laser / Pico Laser
- Chemical peels
- Topical creams
- Oral medication
- Skin booster injections
Another key factor in preventing these pigment spots from worsening is the use of SUNSCREEN. Recommended sunscreen spf: SPF 50+++ / broad spectrum
Prognosis of Treatment
PIH is a benign process but may have significant cosmetic and psychosocial implications.
The condition may take weeks or years to resolve depending on the initial cause, hence why I strongly urge patients to consult a doctor prior to starting their treatments to ensure the right outcome is achievable. Another important factor to weigh in on the treatment outcome is the patient’s skin type.
