Is platelet‑rich plasma (PRP) indicated for treating early‑stage active inflammatory scarring (cicatricial) alopecia that has failed conventional anti‑inflammatory therapy?

PRP for Scarring Alopecia: Clinical Indication

PRP may be considered as an adjunctive therapy for early-stage active inflammatory scarring alopecia that has failed conventional anti-inflammatory treatment, though the evidence base remains limited and standardization is lacking. 1, 2, 3

Evidence Quality and Current Status

The evidence supporting PRP in cicatricial (scarring) alopecia is substantially weaker than for androgenetic alopecia:

• Only 19 patients with primary cicatricial alopecias have been studied across the systematic literature, compared to hundreds for non-scarring conditions 3
• PRP demonstrated efficacy in alleviating disease progression in lymphocytic subtypes (lichen planopilaris, frontal fibrosing alopecia) and neutrophilic subtypes across nine studies 3
• The mechanism appears to involve anti-inflammatory effects and tissue regeneration, which may help stabilize active inflammation 1, 2

When to Consider PRP in Scarring Alopecia

Appropriate clinical scenarios include:

• Early-stage active inflammatory disease with documented progression despite conventional therapy (topical/intralesional corticosteroids, hydroxychloroquine, or other immunosuppressants) 1, 3
• Lymphocytic cicatricial alopecias (lichen planopilaris, frontal fibrosing alopecia) where inflammation is still present 3
• As adjunctive therapy, not monotherapy—continue background anti-inflammatory treatment 3

Treatment Protocol for Scarring Alopecia

Initial treatment phase:

• 3-5 sessions spaced 1 month apart 4, 5
• 5-7 mL PRP per session using 0.05 to 0.1 mL/cm² 4, 5
• Injections 1 cm apart at 90-degree angle, 2-4 mm depth using 30G × 4 mm needles 4, 5, 6
• Target platelet concentration: 1.0-1.5 million platelets per microliter 4, 5
• Manual double-spin preparation method without activation 4, 6

Maintenance phase:

• One session every 6 months after completing initial series 4, 5, 6

Pain management:

• Pharmaceutical-grade topical anesthetic cream is highly recommended given the multiple injections required 4, 7

Critical Limitations and Pitfalls

Major caveats for scarring alopecia specifically:

• No high-quality randomized controlled trials exist for PRP in cicatricial alopecias—most evidence comes from case series and small observational studies 3
• PRP cannot reverse established scarring—it may only stabilize active inflammation and potentially slow progression 1, 3
• Treatment failure is common if disease is advanced or fibrosis is already established 3
• Standardized protocols for cicatricial alopecia do not exist—the protocols above are extrapolated from androgenetic alopecia guidelines 4, 3

Realistic expectations:

• The goal is disease stabilization and slowing progression, not hair regrowth in scarred areas 3
• Objective outcome measures (trichoscopy, scalp biopsy showing reduced inflammation) should guide continuation decisions 3
• If no stabilization occurs after 3-6 months, discontinue PRP and escalate systemic immunosuppression 3

Comparison to Established Evidence

The contrast with non-scarring alopecia is stark:

• Androgenetic alopecia has 389 patients studied with consistent efficacy data 8
• Alopecia areata has 71 patients studied with 31-76% efficacy rates 8, 9
• Cicatricial alopecia has only 19 patients studied with heterogeneous outcomes 3

Therefore, PRP in scarring alopecia should be positioned as an experimental adjunctive therapy for motivated patients who understand the limited evidence base and realistic goals of disease stabilization rather than regrowth. 1, 2, 3