What is the recommended management approach for post-inflammatory hyperpigmentation (PIH)?

Management of Post-inflammatory Hyperpigmentation (PIH)

Chemical peels, particularly glycolic acid and salicylic acid peels, are the most effective first-line treatment options for post-inflammatory hyperpigmentation (PIH), with superior results compared to other modalities. 1

First-Line Treatments

• Topical retinoids are recommended as first-line therapy for PIH due to their ability to increase keratinocyte turnover, making them particularly effective for epidermal PIH 1, 2
• Azelaic acid is recommended for postinflammatory dyspigmentation, especially in acne patients 1, 3
• Topical tyrosinase inhibitors effectively lighten areas of hypermelanosis, including:
  • Hydroquinone (typically 4% cream used twice daily for up to 6 months) 3, 4
  • Kojic acid, arbutin, and certain licorice extracts 3
• Combination therapy shows higher efficacy than single treatments alone, with well-tolerated side effects and low recurrence rates 5
• Photoprotection is essential during PIH treatment - sunscreen (SPF 15 or greater) or protective clothing should be used to prevent repigmentation 6

Procedural Interventions

• Chemical peels have demonstrated superior efficacy compared to other treatments 1, 7:
  • Glycolic acid peels (20-70%)
  • Salicylic acid peels (20-30%) - particularly effective for PIH secondary to acne
• Combination approaches achieve partial response in 84.9% of patients compared to topicals alone (72.4%) or laser/energy-based devices (61.2%) 7

Treatment Algorithm

1. Initial assessment: Determine PIH severity and location
2. First-line therapy:
   • Start with topical agents (retinoids, azelaic acid, or hydroquinone)
   • Ensure strict photoprotection with broad-spectrum sunscreen
3. For resistant cases:
   • Add chemical peels (glycolic acid or salicylic acid)
   • Consider combination therapy with multiple agents
4. Maintenance therapy:
   • Continue with non-hydroquinone agents after initial improvement 1
   • Maintain strict sun protection

Important Considerations and Cautions

• Hydroquinone safety: Test for skin sensitivity before using by applying a small amount to unbroken skin and checking within 24 hours 6
• Avoid irritation: Irritation from treatments can worsen PIH; consider short drug holidays if irritation occurs 3, 4
• Treatment expectations: Primary lesions typically improve weeks before PIH resolves - manage patient expectations to reduce frustration 2
• Monitoring: Regular follow-up is necessary to assess treatment efficacy and adjust as needed
• Duration: PIH treatment often requires several months of consistent therapy for optimal results 4

Special Considerations for Skin of Color

• PIH affects darker-skinned patients with greater frequency and severity 3
• Start topical retinoids early unless contraindicated in patients with skin of color 2
• Use moisturizers to reduce irritation from topical treatments 2
• Caution with procedures to prevent worsening of hyperpigmentation 3