Post-Inflammatory Hyperpigmentation (PIH): A Complete Guide

Post inflammatory hyperpigmentation, commonly known as PIH, refers to dark marks that appear on the skin after wounds, insect bites, pimples or rashes have healed.

These spots develop due to an overproduction of melanin, causing uneven patches of skin color that can persist for months.

Post Inflammatory Hyperpigmentation

Understanding PIH’s causes and treatment options is essential to clearing it up.

This article explains exactly what you need to know to effectively fade dark PIH spots on your face and body.

What is Post-inflammatory Hyperpigmentation (PIH)?

Post-inflammatory hyperpigmentation (PIH) refers to the darkening of the skin that often occurs after an injury or inflammation from conditions like acne, burns, cuts or insect bites.

When the skin is wounded or irritated, it overproduces melanin – the pigment that gives skin its color.

This increased melanin production causes surrounding skin to appear darker over time, resulting in uneven skin tone.

PIH is very common, especially in individuals with darker skin types.

Understanding its causes and treatment options is key to reducing or preventing its appearance.

What Causes Post-Inflammatory Hyperpigmentation & Who Is Most At Risk?

PIH occurs when melanin production increases at the site of healed skin trauma in response to inflammation.

This overproduction results in a dysregulation that leaves behind a dark mark.

Dark Spots from PIH on the Back

Factors that raise PIH risk include:

  • Genetics: Skin of color is more vulnerable due to higher baseline melanin levels.
  • Frequency of injuries or breakouts: More past wounds raise cumulative risk of dyspigmentation.
  • Sun exposure: UV rays stimulate melanocytes to produce even more pigment.
  • Picking or rubbing injuries: Trauma prolongs inflammation leading to darker spots.

The marks can surface weeks after the initial outbreak or injury and may darken further before eventually fading on their own over 3-6+ months.

PIH doesn’t just happen from bites, acne, or cuts, either. It can occur from even the most trivial skincare treatments as well.

For example, you can develop dark armpits after waxing, hyperpigmentation from shaving, PIH after you get microneedling, and even get darker skin patches after laser hair removal.

Treatment Options for PIH That Actually Work

While PIH spots often resolve naturally given time, here are some proven medical and natural remedies to help accelerate fading:

Hydroquinone: Prescription-strength 2% hydroquinone safely inhibits tyrosinase enzyme activity to reduce melanin formation at treated areas. Most effective but potential for irritation.

Retinoids: Dermatologist-grade retinoids like tretinoin stimulate cell turnover to boost collagen and quicker dispersion of melanosomes in the skin.

Kojic Acid: This OTC whitening acid inhibits tyrosinase similarly to hydroquinone but more gently. Best combined with other ingredients.

Vitamin C: Potent antioxidants combat free radicals and boost collagen to quicken spot clearing and prevent re-pigmentation.

AHA/BHA Exfoliation: Salicylic or glycolic acids aid in shedding debris and dead skin cells trapping excess melanin for brighter skin. Getting a TCA peel can work wonders for hyperpigmentation.

Niacinamide: Reduces pigment transfer and blocks UV rays from aggravating PIH over time.

Laser Treatment for Post Inflammatory Hyperpigmentation

Other options to consider for reducing hyperpigmentation include:

  • Laser or light therapies: Intense Pulsed Light (IPL), laser resurfacing and photofacials use targeted light energy to disrupt pigmented layers over sessions.
  • Natural remedies: Lemon juice, licorice extract, arbutin and kojic acid supplements assist lightening when applied topically in combination with other protocols. Always patch test.
  • Camoflaging makeup: Can help disguise areas until prescription fading treatments take full effect over weeks or months of dedicated use.

There are also numerous skin lightening creams and dark spot correctors that do an excellent job of helping fade PIH spots quickly. Some of our favorites are Civant Meladerm, Alchimie Forever Pigment Lightening Serum, and Pearl Bright Dark Spot Corrector.

Always wear SPF 30-50 sunscreen daily as UV rays stimulate melanin production and darken marks further whether using medicated lighteners or natural remedies.

Consulting a dermatologist is wise for moderate-severe cases.

With diligent treatment over 6+ months, dark spots from PIH eventually fade fully.


Q: How long does it take for PIH to appear after an outbreak/wound?

A: PIH spots typically surface 1-4 weeks following skin trauma as melanin production increases at the injury site post-healing.

Q: How long do PIH marks usually last untreated?

A: Without treatment, PIH dark spots may fade partially on their own in 3-6 months. Stubborn cases can persist for a year or longer.

Q: What skin types are most prone to PIH?

A: Skin of color is inherently at higher risk due to naturally higher melanin levels. Those with acne or eczema also tend to be more vulnerable due to frequent wounding/inflammation.

Q: How often should you exfoliate PIH spots weekly?

A: No more than 2-3 times per week max when using chemical exfoliants to treat PIH. Over-exfoliating can further aggravate the skin.

Q: Can PIH scarring occur?

A: Dark marks from severe inflammation/trauma may depigment and flatten into scars. Seeking prompt medical care for deep wounds helps prevent permanent scarring.

What is Post Inflammatory Hyperpigmentation

Q: How long until you see fading of PIH spots?

A: When consistently using recommended creams, serums and SPF, most notice a reduction in darkness within 4-8 weeks. Fully clearing spots takes several months.

Q: If pregnant/breastfeeding, what natural options are safest for PIH?

A: Topical vitamin C, niacinamide, licorice extract and minimal daily SPF are generally considered safest alternatives during this period. Always check with your doctor first.

Q: Can PIH be prevented entirely once prone to it?

A: Proper outbreak treatment, gentle exfoliation and diligent SPF usage helps reduce risk over time. Genetics still plays a role, so it may not be 100% avoidable for certain skin types.

Q: Once PIH is gone, will it come back?

A: PIH spots tend to recur more readily if underlying issues like acne, eczema or injury wounds are not properly managed with a maintenance skincare routine and lifestyle habits. Recurrence risk decreases significantly with time.