Acne scars can be significantly reduced, but the right approach depends entirely on what type of scar you’re dealing with. Indented scars, raised scars, and flat red marks each respond to different treatments, and mixing them up is one of the most common reasons people don’t see results. Most treatments produce noticeable improvement within three to six months, though full results from collagen remodeling can take up to a year.
Identify Your Scar Type First
Before choosing any treatment, you need to know what you’re working with. Acne scars fall into two broad categories: atrophic (indented) and hypertrophic (raised). Within those groups, the specific shape of the scar determines which treatments will actually work.
Ice pick scars are narrow, deep puncture marks that extend far into the skin. They look like someone poked the surface with a sharp instrument. Their depth makes them the most stubborn type to treat with surface-level approaches.
Boxcar scars are wider with sharp, defined edges and flat bases. They can be shallow or deep, and they tend to look like small craters or pockmarks. Shallow boxcar scars respond well to resurfacing treatments.
Rolling scars create a wavy, uneven texture rather than sharp indentations. They’re caused by fibrous bands pulling the skin downward from underneath, which is why surface treatments alone often fall short.
Hypertrophic scars are raised and firm but stay within the boundaries of the original breakout. They may flatten gradually over time on their own. Keloids are a more aggressive version that extends beyond the original wound, can continue growing, and are often itchy or tender.
Flat Red or Brown Marks Aren’t Scars
Many people searching for scar treatments actually have post-inflammatory erythema, which shows up as red or pink discolorations left behind after acne heals. These marks are caused by lingering inflammation and dilated blood vessels in the skin, not by permanent structural damage. They’re most common in lighter skin tones and will fade on their own over weeks to months, though treatments can speed the process.
Pulsed dye lasers target the blood vessel component directly, coagulating the tiny vessels responsible for redness. Intense pulsed light is another option that reduces redness while stimulating some collagen production. If your concern is color rather than texture, these vascular treatments will get you further than scar-focused procedures.
Laser Resurfacing for Moderate to Severe Scars
Lasers are the most studied treatment for atrophic acne scars, and the differences between types matter more than most people realize. In a head-to-head comparison of four laser types, CO2 lasers scored highest for improvement (6.0 out of 10), followed closely by erbium lasers (5.8), then ablative fractional lasers (5.2). Non-ablative fractional lasers scored just 2.2, meaning they produced less than half the visible improvement of the stronger options.
The tradeoff is recovery time. CO2 lasers had the greatest downtime of all four types, with a prolonged healing period and a higher risk of complications like prolonged redness and pigmentation changes. Erbium lasers caused less redness and pigmentation issues while delivering nearly identical improvement scores, making them a practical middle ground for many people.
Ablative fractional lasers work by vaporizing tiny columns of skin tissue while leaving surrounding skin intact, which speeds healing compared to full resurfacing. Non-ablative lasers skip the vaporization step entirely, heating tissue without removing it. That gentler approach explains both the shorter recovery and the significantly lower improvement scores. If your scars are mild, non-ablative may be enough. For moderate to severe scarring, ablative options deliver meaningfully better results.
Microneedling for Gradual Improvement
Microneedling uses a device covered in fine needles (typically 1.5mm long) to create controlled micro-injuries that penetrate into the upper layer of the dermis. The needles break apart the collagen bundles responsible for scar tissue, triggering the body’s wound-healing response to produce new, more organized collagen in their place.
In a clinical evaluation, patients who underwent six microneedling sessions at two-week intervals saw 15 to 20 percent improvement after one month. By the three-month mark, improvement jumped to 51 to 60 percent. That trajectory matters: microneedling is not a one-session treatment, and early results underrepresent the final outcome. The collagen remodeling process continues for months after your last session.
Microneedling works best on boxcar and rolling scars. It’s less effective on deep ice pick scars, where the narrow channel of damage extends too far below the surface for needles to fully address. It’s also a reasonable option if you want to avoid the downtime of laser treatments, though the results are generally more modest.
TCA CROSS for Deep Ice Pick Scars
Ice pick scars are notoriously difficult because they’re so narrow and deep. A technique called CROSS (chemical reconstruction of skin scars) was developed specifically for them. A clinician uses a sharpened wooden applicator to press a high-concentration acid directly into each individual scar, triggering thickening and new collagen production deep within the scar channel.
The concentrations used are far higher than a standard chemical peel, typically 65 to 100 percent, which is why this is strictly an in-office procedure. Results build with repeated sessions. In one study using 70 percent concentration, 20 percent of patients saw excellent results after three sessions, rising to 70 percent after six sessions. Patients treated with 100 percent concentration who completed five or six sessions all achieved excellent results. More than 90 percent of cases showed good improvement after three to six courses overall.
Subcision for Rolling Scars
Rolling scars look uneven because fibrous bands beneath the skin are physically pulling the surface downward. No amount of surface resurfacing will fix the problem if those tethers remain intact. Subcision directly addresses this by inserting a needle beneath the scar and sweeping it in a fan-like motion to cut the fibrous strands anchoring the skin. The release allows the depressed skin to lift back toward the surface.
The procedure is done through a tiny puncture next to the scar, and you can sometimes hear a snapping sound as bands are cut. It’s commonly combined with other treatments. Adding a filler beneath the released scar, for instance, can prevent the bands from reattaching and provide immediate volume to the depression.
Fillers for Immediate Volume
Dermal fillers offer the fastest visible improvement for depressed scars by physically filling the indentation from below. One filler is specifically approved for acne scars and has been shown to last around five years, making it a semi-permanent option. Hyaluronic acid fillers, while not specifically approved for acne scars, are sometimes used off-label but only last nine months to two years depending on the area.
Fillers work best for broader depressions like boxcar and rolling scars. They’re not practical for ice pick scars, which are too narrow for injection. They’re also often used alongside subcision or laser treatments rather than as a standalone approach.
Topical Treatments and At-Home Options
Prescription retinoids are the most evidence-backed topical option. A controlled study found that a retinoid-based formulation significantly reduced scar counts over 24 weeks compared to a placebo, where scar counts actually increased. Retinoids work by accelerating cell turnover and promoting collagen production, gradually smoothing shallow scars and improving overall skin texture. They’re most useful for preventing new scars from forming during active acne and for improving mild, shallow scarring.
For raised scars specifically, silicone gel sheets are a well-supported option. Applied for at least 12 hours a day over two to three months, they improve scar texture first, then pigmentation, then height. The mechanism likely involves hydrating the skin’s outer layer in a way that regulates the signals driving excess scar tissue production. They’re inexpensive and low-risk, making them a reasonable first step for hypertrophic scars and keloids before considering injections or laser treatment.
Combining Treatments for Best Results
Most dermatologists treat acne scars with a combination approach rather than relying on a single method. A typical plan for someone with mixed scar types might involve subcision for rolling scars, TCA CROSS for ice pick scars, and laser resurfacing or microneedling for overall texture improvement, all spaced out over several months.
Regardless of which treatments you pursue, patience is essential. Collagen remodeling is a slow biological process. Boxcar and rolling scars typically show noticeable improvement within three to six months of treatment, but the full benefit may not be visible for up to a year. Hypertrophic scars can take several months to a year to flatten. Planning for multiple sessions and a long timeline will set more realistic expectations than hoping for dramatic change from a single visit.