PDRN for Acne Scars: A Regenerative Approach to Scar Treatment

Acne scars affect an estimated 95% of people who experience inflammatory acne, making them one of the most common reasons people seek dermatological treatment. While numerous treatments exist — from laser resurfacing to subcision to microneedling — many patients struggle to achieve satisfactory improvement. PDRN (polydeoxyribonucleotide) offers a regenerative approach that works at the cellular level to remodel scar tissue and restore skin quality.

Understanding Acne Scars

Acne scars form when inflammatory acne damages the dermis and the body's repair process produces either too little collagen (atrophic scars) or too much (hypertrophic and keloid scars). The vast majority of acne scars are atrophic — depressed below the surface due to collagen loss ^[5].

Atrophic acne scars are classified into three types:

• Ice pick scars: Narrow, deep, V-shaped pits extending into the dermis. The most difficult to treat due to their depth and narrow morphology.
• Boxcar scars: Wide, rectangular depressions with sharp, defined edges. Respond well to treatments that stimulate dermal remodeling.
• Rolling scars: Broad, shallow undulations caused by fibrous bands tethering the skin to subcutaneous tissue. The most responsive to collagen-stimulating treatments.

How PDRN Addresses Acne Scars

PDRN's approach to scar treatment is fundamentally regenerative — rather than destroying tissue to trigger a wound-healing response (as lasers do) or physically releasing tethered tissue (as subcision does), PDRN biologically stimulates the skin's own repair mechanisms to remodel scar tissue from within ^[1][2].

Collagen remodeling

The primary mechanism by which PDRN improves acne scars is through stimulation of new collagen production in the scarred dermis. Via adenosine A2A receptor activation, PDRN triggers fibroblast proliferation and upregulates type I and type III procollagen synthesis. In atrophic scars, this new collagen fills in the dermal deficit, raising depressed scar tissue closer to the surrounding skin level ^[1][4].

Extracellular matrix restoration

Acne scars involve not just collagen loss but disruption of the entire dermal extracellular matrix — including elastin, glycosaminoglycans, and structural proteoglycans. PDRN stimulates fibroblasts to produce a more complete ECM, restoring the normal tissue architecture rather than just adding bulk collagen ^[4].

Anti-inflammatory microenvironment

Many acne scars are surrounded by persistent low-grade inflammation that impairs the skin's ability to remodel and repair. PDRN's potent anti-inflammatory effect — NF-κB suppression, TNF-α and IL-6 reduction through A2A signaling — creates the calm tissue environment necessary for productive scar remodeling rather than continued degradation ^[2][6].

Microcirculation improvement

Scar tissue typically has poor blood supply compared to normal skin. PDRN's VEGF-upregulating effect improves microcirculation in and around scars, enhancing nutrient delivery and waste removal that support the remodeling process ^[7].

Which Acne Scars Respond Best to PDRN?

Best response:

• Rolling scars (broad, shallow undulations)
• Shallow boxcar scars
• Post-inflammatory textural irregularities
• Overall uneven, rough post-acne skin texture

Moderate response:

• Moderate boxcar scars
• Mixed scarring patterns (most patients have a combination)

Limited response as standalone treatment:

• Deep ice pick scars (benefit more from TCA CROSS, punch excision, or fractional laser; PDRN can be used as adjunct)
• Deep, sharply defined boxcar scars (may need subcision + PDRN combination)
• Hypertrophic and keloid scars (different pathology requiring different approach)

Rejuran S: PDRN Designed for Scars

Rejuran S is a specialized PDRN formulation specifically designed for acne scar treatment. It differs from the standard Rejuran Healer in formulation:

• Higher viscosity — the thicker gel provides better structural support when injected directly into depressed scars, acting as a scaffold for tissue regeneration
• Targeted delivery — designed for focused injection into individual scars rather than widespread nappage
• Same PDRN mechanism — the regenerative biology is identical, but the delivery characteristics are optimized for scar treatment

The injection technique for Rejuran S involves direct placement of the product into the base of each depressed scar, filling the deficit while simultaneously triggering collagen regeneration. Over 4–8 weeks, the PDRN stimulates new collagen formation that gradually replaces the injected gel, resulting in long-lasting tissue volume recovery in the scarred area.

Treatment Protocol for Acne Scars

A typical PDRN scar treatment protocol involves:

1. Assessment and grading. Scars are mapped and classified by type, depth, and distribution. A customized treatment plan is created based on the specific scar morphology.
2. Treatment sessions. 4–6 sessions spaced 2–4 weeks apart. Rejuran S is injected directly into depressed scars, while Rejuran Healer is used in nappage technique across the broader treatment area for overall skin quality improvement.
3. Combination approach. For optimal results, PDRN is often combined with other scar treatments:

• Microneedling + PDRN: Microneedling creates controlled micro-injuries that stimulate collagen while PDRN provides the regenerative stimulus and building blocks for repair
• Fractional laser + PDRN: Laser creates deeper tissue remodeling while PDRN accelerates healing and enhances collagen production
• Subcision + PDRN: Subcision releases tethered rolling scars while PDRN fills the created space with new collagen

1. Maintenance. After the initial course, maintenance sessions every 2–3 months help sustain collagen remodeling in the treated areas.

PDRN vs. Other Acne Scar Treatments

Treatment	Mechanism	Best for	Downtime	Sessions needed
PDRN injection	Regenerative collagen stimulation	Rolling/boxcar scars, texture	1–2 days	4–6
Fractional CO2 laser	Thermal tissue remodeling	All scar types	5–10 days	3–5
Microneedling	Controlled wound healing	Mild–moderate scars	2–3 days	4–6
Subcision	Release fibrous tethers	Rolling scars	3–7 days	1–3
TCA CROSS	Chemical reconstruction of individual scars	Ice pick scars	5–7 days	3–6
Dermal filler	Volume replacement	Individual deep scars	0–1 days	1 (temporary)

PDRN's advantage is its biological mechanism — it triggers actual tissue regeneration rather than relying solely on wound healing or temporary volume. The trade-off is that PDRN produces gradual results that require patience and multiple sessions.

What Patients Can Realistically Expect

Based on clinical data, a complete PDRN treatment course (4–6 sessions) for acne scars typically produces ^[1][3]:

• 20–40% improvement in overall scar appearance (measured by scar grading scales)
• Significant texture smoothing — the rough, irregular post-acne surface becomes notably smoother
• Reduced shadow casting — shallow scars become less visible as collagen fills in the depressions
• Improved skin quality — beyond scar improvement, the surrounding skin looks healthier, more hydrated, and more luminous

PDRN alone does not usually achieve 80–100% scar clearance. For the best possible results with moderate to severe acne scarring, combine PDRN with complementary treatments (laser, microneedling, or subcision) in a multimodal approach. Many dermatologists use PDRN as the regenerative foundation of a comprehensive scar treatment protocol.

Tips for Maximizing PDRN Results for Acne Scars

1. Complete the full course. Results are cumulative — stopping early means leaving collagen remodeling potential on the table.
2. Use topical PDRN between sessions. Daily application of PDRN serum maintains regenerative stimulation between professional treatments.
3. Protect from sun. UV exposure degrades new collagen and can worsen post-inflammatory pigmentation around scars. SPF 50+ daily is non-negotiable.
4. Be patient. Collagen remodeling peaks at 2–3 months post-treatment and continues for up to 6 months. Final results take time.
5. Consider combination treatments. PDRN + microneedling or PDRN + fractional laser produces better outcomes than any single treatment for moderate to severe scarring.
6. Manage active acne first. Ensure your acne is well-controlled before investing in scar treatment. Treating scars while new breakouts continue is counterproductive.