Acne scars form when deep inflammation damages the collagen and structure of the skin, and once the wound heals the surface stays sunken, pitted, or uneven. No single treatment erases them, but several procedures have real clinical evidence behind partial improvement, and the right choice depends heavily on the type of scar you have. This guide walks through what each treatment actually does, how strong the proof is, where the research is weak or industry-funded, and who is most likely to benefit.
First: what kind of scar do you have?
This matters more than almost anything else. A treatment that works well for a wide, shallow scar can do nothing for a narrow, deep one. Most acne scars fall into a few buckets, and clinicians sort "atrophic" (sunken) scars into three shapes.
| Scar type | What it looks like | Rough share of atrophic scars | Responds best to |
|---|---|---|---|
| Ice pick | Narrow (under 2 mm), deep, V-shaped pits that taper to a point | ~60-70% | TCA CROSS, punch excision |
| Boxcar | Wider (1-4 mm), round or oval craters with sharp vertical walls | ~20-30% | Lasers, microneedling, radiofrequency, fillers |
| Rolling | Broad, shallow, wavy dips caused by tethering under the skin | ~15-25% | Subcision, microneedling, fillers |
| Hypertrophic / keloid | Raised, thick scars (more common on chest, back, jaw) | varies | Steroid injection, not resurfacing |
Atrophic (sunken) scars are by far the most common from facial acne, and the depressions happen because too little collagen rebuilt during healing. Hypertrophic and keloid scars are the opposite problem — too much collagen — and they need a completely different approach, usually corticosteroid injections rather than the resurfacing treatments below.
Most people have a mix of scar types on one face. That is the single biggest reason dermatologists rarely rely on one treatment alone. The American Academy of Dermatology notes that an individualized plan, often combining more than one procedure, gives the best results.
How acne scars form (the mechanism)
Inflammatory acne — the deep, painful kind — triggers an immune response that breaks down collagen and fat in the dermis, the layer beneath the surface skin. When the breakout heals, the body tries to rebuild that lost tissue. If it rebuilds too little, the skin caves in and you get an atrophic scar. If it overshoots, you get a raised scar.
Every effective scar treatment works on the same basic principle: create a small, controlled injury that prompts the body to lay down fresh collagen and remodel the scar tissue. Lasers do it with heat. Microneedling does it with tiny punctures. Subcision does it by cutting the tethers that pull a scar down. Chemical peels do it by destroying and resurfacing a thin layer of skin. The differences come down to how deep the injury goes, how precise it is, and how much downtime and risk come with it.
Because the process depends on your own collagen response, results build slowly over months, and they vary from person to person. This is also why no honest provider can promise complete removal.
It also explains why timing matters. Treating scars while acne is still flaring is largely a waste of money — fresh inflammation keeps damaging collagen and can even create new scars near a treatment site. Most dermatologists insist that active acne be controlled first, which is one reason the American Academy of Dermatology guidelines for acne put strong emphasis on retinoids, benzoyl peroxide, and oral isotretinoin for scarring or severe disease before any resurfacing work begins. Clearing the acne is itself a scar-prevention strategy.
One more thing to understand about mechanism: depth. A scar that runs deep into the dermis, like an ice pick scar, cannot be fixed by a treatment that only resurfaces the top layer. That mismatch — deep scar, shallow treatment — is the most common reason people feel like a procedure "didn't work." It often did exactly what it was designed to do; it just couldn't reach the problem.
The treatments, ranked by evidence
Microneedling
What it is: A device rolls or stamps fine needles into the skin to create thousands of microscopic channels, which kick off collagen production.
The evidence: This is one of the better-studied options. A systematic review of nine randomized controlled trials (341 patients) found microneedling consistently improved atrophic acne scars, whether used alone or combined with other treatments, with improvement visible after as few as three sessions. In head-to-head comparisons it performed about as well as 100% TCA CROSS and a 1550 nm fractional laser, while an Er:YAG laser slightly outperformed it.
Honest grading: Moderate. The trials were small (the largest had 60 patients), follow-up was short, and the authors could not pool the data into a formal meta-analysis because the studies measured outcomes so differently. So the direction of the evidence is solid, but the precision is not. Pain tolerance is a genuine plus — in a large network meta-analysis, microneedling ranked as the most tolerable option for patients.
Best for: Boxcar and rolling scars; all skin tones (it carries a lower pigmentation risk than lasers).
For a deeper walkthrough of devices and session schedules, see our microneedling guide.
Fractional lasers (CO2, Er:YAG, non-ablative)
What it is: A laser delivers columns of heat into the skin, leaving healthy tissue between them to speed healing. "Ablative" lasers (CO2, Er:YAG) remove tissue; "non-ablative" lasers heat without removing it, trading some power for less downtime.
The evidence: Across systematic reviews, most patients treated with fractional CO2 laser see roughly 30-70% improvement in scar appearance. Lasers also tend to rank near the top of network meta-analyses, especially when combined with another therapy.
Honest grading: Moderate to good for efficacy, but with a clear safety caveat. The most important: in darker skin (Fitzpatrick types III-VI), fractional CO2 laser carries a high risk of post-inflammatory hyperpigmentation (PIH), with some studies reporting PIH in around 30% of treated patients. That dark-spot reaction can last months. It is manageable with conservative settings, pre-treatment with peels or pigment-suppressing creams, and an experienced provider — but it is real, and it is the main reason laser is not a default choice for everyone.
A note on the different laser types: ablative CO2 lasers hit hardest and tend to give the biggest improvement per session, but they also bring the longest downtime (a week or more of raw, peeling skin) and the highest pigment risk. Er:YAG lasers are slightly gentler with somewhat faster healing. Non-ablative fractional lasers (such as 1550 nm devices) trade power for safety — less downtime, lower pigment risk, but you usually need more sessions to match what an ablative laser does. For darker skin, that safety trade often makes non-ablative or microneedling-based options the smarter first move.
Best for: Boxcar and rolling scars, mainly in lighter skin tones, or in darker skin only with a cautious provider and careful settings.
See our microneedling vs chemical peel comparison for how energy and chemical resurfacing stack up, and our chemical peel for acne breakdown for matching acid strength to scar depth.
Subcision
What it is: A needle or blunt cannula is inserted under a scar and moved in a fanning motion to cut the fibrous bands that tether the scar down, releasing it so the surface can lift.
The evidence: Subcision is the go-to procedure for rolling scars, because those scars are defined by under-the-skin tethering. In one study of 40 patients, both patients and investigators rated overall improvement around 50%. The catch: subcision alone tends to give modest results, and scars can re-tether over time. Combining it with other treatments works better — pairing subcision with PRP, for example, produced markedly more improvement than subcision alone in controlled work. See the broader evidence on subcision for acne scars.
Honest grading: Moderate, and strongest specifically for rolling scars. Evidence for subcision alone is modest; the case for subcision as part of a combination is more convincing.
Best for: Rolling scars, and boxcar scars with deep tethering. Not useful for ice pick scars.
TCA CROSS (for ice pick scars)
What it is: "CROSS" stands for Chemical Reconstruction of Skin Scars. A tiny drop of high-strength trichloroacetic acid (often 100%) is applied with a fine wooden tip directly into the bottom of a deep, narrow scar — and nowhere else.
The evidence: Ice pick scars are notoriously hard to treat because they run too deep for resurfacing to reach. TCA CROSS is one of the few methods that targets them. In an assessment of the CROSS technique with 100% TCA, more than 70% improvement was seen in 8 of 10 evaluated patients, with the rest showing 50-70% improvement, across four sessions spaced two weeks apart.
Honest grading: Promising but built on small studies. The trials are tiny and largely uncontrolled, so the impressive numbers should be read as encouraging rather than definitive. Because it spot-treats individual scars, it spares surrounding skin, which keeps the pigmentation risk lower than full-field laser — though transient light or dark spots were still reported.
Best for: Ice pick scars specifically. This is its niche, and few other treatments do it well.
Radiofrequency microneedling (RF microneedling)
What it is: Microneedles that also deliver radiofrequency heat at their tips, combining mechanical puncture with thermal collagen stimulation deeper in the skin.
The evidence: A 2025 systematic review of RF microneedling as a standalone treatment concluded it is likely effective for acne scarring on its own. A potential advantage in darker skin: because the energy is delivered below the surface and largely spares the pigment-producing top layer, it may carry less hyperpigmentation risk than ablative lasers — though this needs more direct comparison.
Honest grading: Moderate and growing, but the field is still sorting out whether RF microneedling beats plain microneedling or fractional laser, and whether combining it with laser adds enough to justify the cost. Several reviews call those combination questions genuinely unresolved.
Best for: Boxcar and rolling scars; a reasonable option for medium-to-dark skin.
Platelet-rich plasma (PRP) as an add-on
What it is: Blood is drawn, spun in a centrifuge to concentrate platelets and growth factors, then applied to or injected into the skin alongside microneedling, subcision, or laser.
The evidence: PRP is best understood as an adjunct, not a standalone treatment. A meta-analysis of microneedling with versus without PRP found that adding PRP nearly tripled the odds of better than 50% improvement (odds ratio about 2.97). Several reviews report similar adjunctive benefits when PRP is paired with subcision or fractional laser.
Honest grading: Mixed, and this is where you should be most skeptical. The studies vary wildly in how the PRP was prepared (single-spin vs. double-spin yield different concentrations), how it was applied, and how outcomes were scored. Between-study differences were large enough that some reviewers could not combine the data at all. PRP is also a heavily marketed, cash-pay add-on, so commercial incentives push it harder than the evidence strictly supports. It probably helps a bit as an add-on; it is not a reason to skip the base procedure.
Best for: As an extra layer on top of microneedling, subcision, or laser — not on its own.
Chemical peels
What it is: An acid solution (glycolic, salicylic, Jessner's, or TCA at varying strengths) removes the outer skin layers to prompt resurfacing. Medium-depth peels reach further than superficial ones.
The evidence: Peels can modestly improve shallow atrophic scars and surface texture, and they pair well with other procedures. They are most useful for mild scarring, uneven tone, and post-acne discoloration rather than deep pits.
Honest grading: Mild benefit for shallow scarring; weaker for deep scars. Reliable as a low-risk, lower-cost adjunct.
Best for: Mild, shallow scarring and post-acne pigmentation. Read our chemical peel guide for depth and acid choices.
Topical retinoids
What it is: Prescription or over-the-counter vitamin A creams (tretinoin, adapalene, trifarotene) that speed cell turnover and stimulate collagen.
The evidence: Retinoids are the only at-home option with meaningful scar data. The START study of trifarotene, a 24-week split-face trial, found the retinoid cut atrophic scar count by about 55% versus 30% for the vehicle cream, with a difference appearing as early as week 2. A broader review of topical retinoids for acne scars credits their collagen-stimulating action for modest improvement and for preventing new scars by controlling active acne.
Honest grading: Good for prevention and mild improvement; not a fix for established deep scars. Their biggest value may be heading off future scarring by keeping acne under control.
Best for: Anyone with active or recent acne, and as maintenance between procedures.
Dermal fillers
What it is: Injectable gel (usually hyaluronic acid) is placed under a depressed scar to physically lift it.
The evidence: Fillers give immediate improvement for rolling and some boxcar scars, but most are temporary and need repeating. They do not remodel the scar; they pad it.
Honest grading: Reliable for short-term lift, limited as a permanent solution.
Best for: Rolling and shallow boxcar scars, and quick results before an event.
What the head-to-head evidence says overall
The largest synthesis to date is a network meta-analysis of 68 randomized trials and 4,480 patients. Its core takeaways:
| Outcome | Top-ranked approach | Honest caveat |
|---|---|---|
| Scar severity (ECCA score) | Laser + PRP | Combination beat monotherapies, but confidence intervals were wide |
| Physician scar scale | Laser + drugs, laser + filler | Differences often crossed zero — not statistically firm |
| Patient satisfaction | Laser + chemical peel | Outperformed laser, microneedling, and peels used alone |
| Lowest pain | Microneedling | Best tolerated, though not statistically separated |
| Side effects | No clear winner | No treatment clearly reduced redness or PIH versus others |
The headline pattern across nearly every quality review is the same: combination treatment beats any single modality, and lasers paired with another therapy tend to rank highest. But the same reviews repeatedly flag that confidence intervals overlap, study quality is uneven, and outcome scales are inconsistent. So "laser plus something" is a reasonable bet, not a proven hierarchy.
It is worth being clear-eyed about why the evidence stays this fuzzy. Acne scar studies are usually small, often run at a single clinic, and frequently use a split-face design where one side of the face gets treatment A and the other gets treatment B. Split-face designs are clever and reduce variation between people, but they also limit sample size and can let heat or healing factors "bleed" across the midline. On top of that, researchers grade scars with at least half a dozen different scales — ECCA, Goodman and Baron, physician global assessment, patient satisfaction — which makes pooling results across studies genuinely hard. And a meaningful share of procedural research is funded or run by the companies that sell the devices or the PRP kits. None of this means the treatments don't work. It means the precise ranking of one against another is softer than glossy marketing suggests, and you should weight a provider's experience and your specific scar type more heavily than any single "best treatment" claim. The honest summary: several of these treatments clearly help, the magnitude is moderate, and combinations tend to edge out solo treatments.
Safety, downtime, and realistic expectations
Every resurfacing treatment carries some redness, swelling, and peeling for days to weeks. The serious risks worth weighing:
- Post-inflammatory hyperpigmentation (PIH): Dark spots that appear after the procedure, most common in medium-to-dark skin, especially after ablative lasers. Often fades over months but can be stubborn. This is the single most important factor when choosing between laser and gentler options if you have darker skin.
- Infection or prolonged redness: Rare with proper aftercare and sterile technique.
- Scarring from the treatment itself: Uncommon, but more likely with aggressive settings or an inexperienced provider.
- Disappointing results: Realistically, most treatments deliver partial improvement — think 30-70% better, not gone. Several sessions are usually needed.
Two practical rules from the evidence. First, match the treatment to the scar type — ice pick scars need TCA CROSS or excision, rolling scars need subcision, and broad resurfacing won't fix either. Second, if you have darker skin, prioritize providers experienced with skin of color, and ask specifically how they prevent PIH.
Who each treatment is for
- Active or recent acne: Get the acne controlled first (often with retinoids, and severe cases with a dermatologist). Treating scars while acne is active is like patching a roof in the rain.
- Ice pick scars: TCA CROSS or punch excision.
- Rolling scars: Subcision, often combined with microneedling or PRP; fillers for quick lift.
- Boxcar scars: Microneedling, RF microneedling, or fractional laser.
- Darker skin tones: Favor microneedling, RF microneedling, and TCA CROSS over ablative laser; if laser is used, insist on conservative settings and PIH prevention.
- Mild scarring or discoloration: Chemical peels and topical retinoids.
- Budget-conscious or downtime-averse: Start with retinoids and microneedling before considering laser.
Frequently Asked Questions
Can acne scars be removed completely?
No. Be wary of anyone who promises total removal. The realistic goal is meaningful improvement — across systematic reviews, most effective treatments deliver roughly 30-70% better appearance, usually over several sessions. Scars become much less noticeable, but some residual texture typically remains.
Which treatment is best for my type of scar?
It depends entirely on the shape. Ice pick scars respond to TCA CROSS or punch excision; rolling scars to subcision; boxcar scars to microneedling, RF microneedling, or fractional laser. Most people have a mix, which is why dermatologists usually combine treatments rather than rely on one.
Is laser or microneedling better for acne scars?
Both have solid evidence and often perform comparably for boxcar and rolling scars. Lasers can be more powerful and tend to rank higher in head-to-head reviews, but they carry a higher risk of hyperpigmentation, especially in darker skin. Microneedling is gentler, better tolerated, and lower-risk for pigment changes, which makes it a safer starting point for many people.
Does PRP ("vampire facial") actually work for scars?
The evidence suggests PRP helps modestly as an add-on to microneedling, subcision, or laser — not on its own. Studies show adding PRP improves results, but they vary widely in preparation and quality, and PRP is heavily marketed as a premium upcharge. Treat it as a possible bonus, not a must-have.
How many sessions will I need and when will I see results?
Most procedural treatments require three to six sessions spaced about four to six weeks apart. Because results depend on your skin slowly building new collagen, improvement appears gradually over three to six months and continues after the final session. Topical retinoids likewise take months of daily use.
This article is for general education and is not medical advice. Acne scarring is a medical condition; consult a board-certified dermatologist to evaluate your skin and choose a treatment plan.