Written by Dr Gerard Ee, MBBS (UK), MRCS (Edinburgh), PGDip Practical Dermatology (Cardiff). Last medically reviewed and updated: September 2026.
Microneedling is the acne scar treatment most patients try first, because it is inexpensive, widely offered and presented as gentle. It is effective, and the published trials establish the size of that effect, the patients in whom it is greatest, and what increases it. The evidence is set out below in plain terms, namely the improvement to expect from plain needling, what changes when radiofrequency or platelet-rich plasma (PRP) is added, how needling compares with a laser, and one finding that overturns advice still printed on most clinic websites, this one included until recently. The device pages for Infini and Secret RF describe what happens at an appointment and what it costs, and the acne scar guide sets out the full plan.
Microneedling for acne scars, the evidence in summary
| Plain microneedling | Effective for rolling and boxcar scars. Every patient in the published series improved, by 31 to 62 per cent, over a course [1]. It is also the most comfortable of the scar treatments [2]. |
| Microneedling plus PRP | Roughly triples the odds of an improvement greater than 50 per cent compared with needling alone, without additional side effects [3]. |
| Microneedling plus a peel | Ranked highest of all needling combinations for improvement and satisfaction in a 2024 analysis of 24 trials [4]. |
| RF microneedling vs fractional CO2 | CO2 is slightly more effective. Radiofrequency (RF) needling is two points less painful, heals two days faster and carries a quarter of the darkening risk [5]. |
| Not suitable for | Ice pick scars, keloids and active acne. The at-home roller is also excluded. |
Does microneedling work for acne scars? What the trials report
Microneedling is effective for depressed scars. The needles create controlled columns of injury through the dermis, and the repair response that follows lays down new collagen beneath the depression over the weeks after each session. The systematic review of non-energy scar treatments pooled eight microneedling studies and found that every patient improved, with the improvement in scar appearance ranging from 31 to 62 per cent across the series after a course [1]. That figure is both a genuine result and the ceiling of what needling alone achieves, since microneedling does not remove a scar. The trials reporting the best figures used three to six sessions at four to six week intervals, which is the schedule I follow.
It is also the treatment patients tolerate best. In the largest analysis of acne scar trials to date, covering 68 randomised studies and 4,480 patients, microneedling ranked as the most tolerable of all the treatments compared on pain [2]. For a first course, for a patient who cannot accommodate downtime, or for skin that pigments easily, tolerability matters as much as the improvement figure.
What makes microneedling more effective
The consistent finding across the last five years of research is that microneedling alone establishes the baseline result, and that the treatment combined with it determines how far above that baseline the outcome reaches.
PRP. The patient’s own platelets are concentrated from a blood sample and applied through the channels the needles open. As the platelets break down they release growth factors into the dermis, which is the proposed basis for the additional collagen response. A meta-analysis of fourteen studies and 472 patients found that adding PRP to microneedling gave nearly three times the odds of an improvement of more than 50 per cent on the standard scar scale, roughly four times the odds of patient satisfaction, and no increase in severe redness or swelling [3].
A chemical peel. In a 2024 network meta-analysis of 24 randomised trials and 1,546 patients, microneedling combined with a chemical peel ranked highest of all the needling combinations for improvement, satisfaction and treatment success, ahead of needling with PRP, with hyaluronic acid and with botulinum toxin, and with no difference in side effects between them [4]. The needles allow the acid to reach the dermis evenly, and the acid performs the remodelling that the needles alone cannot.
Radiofrequency. Insulated needles heat the dermis at a set depth while leaving the surface intact. That heating is the difference between a dermaroller and Infini or Secret RF, and it is the reason RF microneedling is compared against lasers rather than against plain needling, a comparison taken up next.
Topical insulin. This remains a research finding rather than a clinic offering. A 2026 meta-analysis of five small trials found that microneedling with topical insulin produced a higher rate of significant improvement than microneedling with PRP, at equivalent safety, although the certainty of the evidence was low and the authors called for larger trials [6]. I mention it because it will appear in marketing before it appears in guidelines.
Microneedling vs laser for acne scars
RF microneedling against fractional CO2 laser is the comparison that decides most treatment plans, and the head-to-head randomised trials were pooled in 2026. Fractional CO2 was more effective by a small margin and rated slightly higher by patients. RF microneedling was two points less painful on a ten-point scale, its redness settled nearly two days sooner, and it carried about a quarter of the risk of post-inflammatory darkening [5]. That difference in darkening risk follows from where the energy is delivered, since insulated RF needles heat the dermis while the surface is left intact, whereas an ablative laser injures the pigment-producing layer directly and it is that injury which provokes the pigment response. Across the broader network of 56 trials and 1,488 patients, the highest-ranked treatments for moderate-to-severe scars were combinations rather than any single device, with CO2 laser plus subcision or PRP the most consistent [7].
Where the scar is the only consideration, the laser has a small advantage. Where the skin is Fitzpatrick III to V, as it is for most Singaporeans, the darkening risk becomes the governing consideration, and RF microneedling is the safer opening treatment, with laser added later at lower settings or a picosecond laser used in its place. The settings for darker skin are set out in the guide.
When microneedling is not appropriate
Ice pick scars are unsuitable, because the needles do not reach the floor of a narrow pit and those scars require TCA CROSS, in which concentrated trichloroacetic acid is placed into each pit. Rolling scars that remain tethered are also unsuitable, since needling over an unreleased band improves the surface and leaves the depression, which is why subcision is performed first. Keloid and hypertrophic scars can be made worse by needling. Active acne is settled before treatment begins, because needling active lesions spreads inflammation. The at-home roller is excluded altogether, as I have set out separately in is at-home microneedling safe. A 0.25 mm roller does not reach a scar, and a deeper one used without sterile technique is a common cause of infection and of new scarring.
The six-month wait after isotretinoin is not supported by current evidence
For thirty years the rule was that anyone who had taken isotretinoin (Roaccutane, Accutane) had to wait six to twelve months before any laser, peel or needling, on the basis of case reports of abnormal scarring from the 1980s. The evidence has since changed, while most clinic websites have not been updated. In 2017 an expert task force reviewed the literature, concluded that there was insufficient evidence for the delay and that the practice should be discontinued, and listed fractional lasers for acne scarring, RF microneedling, peels and dermaroller as safe during or soon after isotretinoin [8]. A 2023 series from China of 511 patients taking isotretinoin or within six months of stopping it, treated with peels, intense pulsed light (IPL), fractional lasers, fractional RF and ablative CO2 over 1,350 sessions, found no keloids and no increase in serious side effects [9]. A 2025 study in Southeast Asian patients with skin types III to V, most of them IV and V, treated acne scars with ablative fractional CO2 during isotretinoin therapy and found that the group taking the drug healed with less crusting and had less post-inflammatory darkening, 24 per cent against 42 per cent, at the same level of scar improvement [10].
My clinical perspective
I no longer require patients to wait. Scars are treated during a course of isotretinoin once the acne is controlled, because each month of delay is a further month in which the scar matures and becomes harder to remodel, and because the evidence in darker skin now points in the opposite direction. Where a clinic advises a six-month wait, it is reasonable to ask which study that advice rests on. The one exception in every review is fully ablative, non-fractional laser and mechanical dermabrasion, which are still not recommended on isotretinoin; none of the treatments on this page is either.
How many microneedling sessions, and what to expect
Plain and RF microneedling are given as three to six sessions at four to six week intervals, with improvement accumulating over the course and for three months after the final session, because the collagen laid down after each session continues to remodel for that period. Redness lasts a day or two after RF needling and somewhat longer after plain needling at depth, and there is no further downtime. Topical anaesthetic keeps the procedure comfortable, and the trials rate microneedling the most tolerable of the scar treatments [2]. Photographs taken before treatment and at the end of the course are how the result is judged, because an improvement of 30 to 50 per cent accrues gradually and is easily overlooked in day-to-day observation.
Frequently asked questions
How effective is microneedling for acne scars?
In the published series every patient improved, by 31 to 62 per cent, over a course of three to six sessions. Adding PRP roughly triples the odds of an improvement greater than 50 per cent, and adding radiofrequency brings the result close to that of a laser.
Is microneedling or laser better for acne scars?
Fractional CO2 is slightly more effective in head-to-head trials. RF microneedling is less painful, heals faster and carries about a quarter of the darkening risk, which usually makes it the preferred first treatment in Singaporean skin.
Does microneedling with PRP work for acne scars?
Yes. In a meta-analysis of 472 patients, microneedling with PRP gave nearly three times the odds of an improvement greater than 50 per cent compared with microneedling alone, and no additional side effects were recorded.
How many microneedling sessions for acne scars?
Three to six sessions are given at four to six week intervals. Results accumulate over the course and for three months after the final session.
Can microneedling make acne scars worse?
Rarely, and in three situations only, namely needling over active acne, needling a patient prone to keloids, and a deep roller used at home without sterile technique. Performed in a clinic on depressed scars, microneedling is one of the safest scar treatments available.
Can I have microneedling while on isotretinoin?
Yes. The 2017 guideline and the 2023 and 2025 studies found no increased risk of scarring or darkening from fractional lasers, RF microneedling or peels during or soon after isotretinoin, and the six-month wait is not supported by current evidence. Only fully ablative, non-fractional laser and mechanical dermabrasion are still not recommended.
Does a dermaroller at home work for acne scars?
No. Home rollers are too shallow to reach a scar, and deeper ones carry a risk of infection and further scarring when used without sterile technique. The clinic treatment uses set depths, sterile single-use cartridges and topical anaesthetic.
Key references
Show the 10 references
1. Kravvas G, Al-Niaimi F. A systematic review of treatments for acne scarring. Part 1: Non-energy-based techniques. Scars Burn Heal. 2017;3:2059513117695312. PubMed
2. Wu B, Gao M, Zhang Y, Bai X. Optimal treatment options for acne scars in patients with historic acne: a systematic review and network meta-analysis. PeerJ. 2025;13:e19938. PubMed
3. Kang C, Lu D. Combined Effect of Microneedling and Platelet-Rich Plasma for the Treatment of Acne Scars: A Meta-Analysis. Front Med (Lausanne). 2021;8:788754. PubMed
4. Li H, Jia B, Zhang X. Comparing the efficacy and safety of microneedling and its combination with other treatments in patients with acne scars: a network meta-analysis of randomized controlled trials. Arch Dermatol Res. 2024;316(8):505. PubMed
5. Argobi Y, Tobeigei F, Alasiri FI. Fractional CO2 Laser Versus Micro Needling Radiofrequency for Post Acne Scarring: A Meta-Analysis of RCTs. J Cosmet Dermatol. 2026;25(3):e70765. PubMed
6. Albazee E, AlOtaibi A, Alsaffar H, et al. Microneedling with Topical Insulin Versus Microneedling with Platelet-rich Plasma for Post-Acne Scars: A Systematic Review and Meta-Analysis with Trial Sequential Analysis. Aesthetic Plast Surg. 2026;50(16):6765-6779. PubMed
7. Ou Y, An G, Liang J, et al. Laser, Microneedling, and Combination Therapies for Moderate to Severe Acne Atrophic Scars: A Systematic Review and Network Meta-Analysis. Aesthetic Plast Surg. 2026. doi:10.1007/s00266-026-06165-8. PubMed
8. Mysore V, Mahadevappa OH, Barua S, et al. Standard Guidelines of Care: Performing Procedures in Patients on or Recently Administered with Isotretinoin. J Cutan Aesthet Surg. 2017;10(4):186-194. PubMed
9. Qin X, Huang H, Zou Y, Yu B, Tu P. Cosmetic therapies for Chinese patients with acne taking concomitant or recent intake of oral isotretinoin: A retrospective study. J Cosmet Dermatol. 2023;22(11):3168-3175. PubMed
10. Rujirawan P, Charoenchaipiyakul K, Krithin S, Washrawirul C, Kumtornrut C. Ablative Fractional CO2 Laser Treatment With and Without Oral Isotretinoin: A Study on Side Effects and Acne Scars Improvement in Southeast Asians. Lasers Surg Med. 2025;57(8):678-684. PubMed
This article is written from published research and my own clinical practice. It is general information and not a substitute for a consultation. Treatment decisions are made after examination.
