Is microneedling with 1.5-2.5mm depth recommended for acne scars in repeated sessions for individuals with rosacea?

Microneedling for Acne Scars in Rosacea Patients

Microneedling at 1.5-2.5mm depth in repeated sessions can be used for acne scars in patients with rosacea, but requires careful consideration and monitoring, as the evidence shows both therapeutic benefit and potential for exacerbation. The procedure has been shown effective for acne scarring while demonstrating safety in rosacea patients when properly performed, though one case report documents rosacea induction following treatment 1.

Evidence Supporting Use in Rosacea

The most compelling evidence comes from a 2021 prospective study demonstrating that non-ablative fractional laser therapy (a comparable controlled injury modality) successfully treated acne scars in 30 rosacea patients without worsening rosacea symptoms. 2 This study showed:

• Median acne scar scores significantly reduced from 45 to 15 after three treatments 2
• Rosacea erythema scores remained stable (2.1 to 1.9, p=0.326) 2
• Flushing, burning, and stinging symptoms did not worsen 2
• 73.3% of patients were satisfied or highly satisfied 2
• No serious adverse effects occurred 2

A 2024 comparative study further supports microneedling radiofrequency as safe and effective for rosacea treatment itself, showing 82.75-91.37% reduction in rosacea severity scores after 16 weeks 3. This demonstrates that controlled dermal injury can actually benefit rosacea patients rather than harm them 3.

Optimal Treatment Protocol

For acne scars, the evidence-based protocol involves 3-4 treatments at 1.5mm depth, spaced 1 month apart, with maintenance every 6 months. 4 The specific technical parameters include:

• Needle depth: 1.5-2.5mm depending on scar severity 4
• Treatment frequency: Sessions every 4 weeks for initial series 4
• Number of sessions: 3-4 initial treatments 4, 5
• Maintenance: Every 6-12 months thereafter 4, 5
• Device specifications: Automated device operating at 3,000-5,000 RPMs 4, 5

Enhanced Results with Adjunctive Therapy

Combining microneedling with autologous platelet concentrates (PRP or PRF) produces significantly superior outcomes compared to microneedling alone. 4, 5 The evidence shows:

• PRF demonstrates 3-fold higher therapeutic response than PRP when combined with microneedling 5
• Combination therapy shows mean improvement of 70.43% versus 48.82% for PRP alone or 39.71% for microneedling alone 4
• Patient satisfaction is significantly higher with combined treatment 4
• APCs deliver growth factors (PDGF, TGF-β) that enhance collagen type 1 expression 5

Critical Safety Considerations for Rosacea Patients

The primary caveat is one documented case of fractional microneedling radiofrequency inducing rosacea in a 61-year-old woman treated for wrinkles. 1 This represents conflicting evidence with the therapeutic studies and warrants caution.

Risk Mitigation Strategies:

• Start conservatively: Begin with shallower depths (1.5mm) and assess tolerance before progressing 4
• Monitor inflammatory response: Rosacea patients should be closely observed for exacerbation of erythema, flushing, or inflammatory lesions 2
• Avoid active flares: Do not perform microneedling during active rosacea exacerbations 4
• Consider adjunctive therapy: The 2024 study showed combining microneedling with low-dose isotretinoin (10mg/day) reduced relapse rates from 32% to 16% 3

Post-Treatment Protocol

Strict post-procedure care is essential to prevent complications in rosacea-prone skin:

• Avoid sunlight for 24 hours post-procedure 4, 5
• Avoid heavily scented facial products for 24 hours 4, 5
• Use gentle, non-comedogenic products during 24-48 hour healing period 4, 5
• Expected downtime is 24-48 hours, significantly shorter than laser alternatives 4, 5

Safety Profile

Microneedling demonstrates excellent overall safety with minimal adverse effects. A 2021 systematic review of 1,029 patients found microneedling is relatively safe with expected temporary effects including erythema, pain, edema, and skin irritation 6. The procedure carries:

• Minimal risk of post-inflammatory hyperpigmentation since maximum penetration is only 2.5mm 4, 5
• Lower scarring risk compared to lasers 4
• Safety across all Fitzpatrick skin types, including types III-VI where lasers may be contraindicated 4, 5

Clinical Decision Algorithm

For rosacea patients with acne scars:

1. Ensure rosacea is well-controlled before initiating microneedling, following phenotype-based management strategies 4
2. Begin with 1.5mm depth for initial treatment to assess tolerance 4
3. Consider combining with PRP/PRF for optimal outcomes 4, 5
4. Schedule 3-4 sessions spaced 4 weeks apart 4, 5
5. Monitor closely for rosacea exacerbation after each session 2
6. Maintain with treatments every 6-12 months once desired improvement achieved 4, 5

The preponderance of evidence supports microneedling as safe and effective for acne scars in rosacea patients when properly executed, though the single case report of rosacea induction mandates informed consent and vigilant monitoring.