Fractional CO2 laser

Also known as: ablative fractional resurfacing, CO2 laser resurfacing

Fractional CO2 is the heavyweight of skin resurfacing: a 10,600 nm laser vaporizes thousands of microscopic columns of skin, leaving intact tissue between them to speed healing. It has the strongest evidence in this category for atrophic acne scars, where meta-analyses show it beats both Er:YAG lasers and RF microneedling, and solid trial support for wrinkles. The trade-off is real downtime and the highest pigmentation risk of the common devices, especially in darker skin.

How it works

The laser's energy is absorbed by water in tissue, instantly vaporizing narrow columns through the epidermis into the dermis and heating the surrounding collagen. The injured columns trigger aggressive collagen remodeling over 3 to 6 months while the untouched skin between columns repopulates the surface within days, which is what makes fractional delivery tolerable compared with old full-field CO2 resurfacing.

What the evidence says, claim by claim

These are the results measured in studies, not the results shown in ads. Where the research is weak, the grade says so.

For acne scars

Strong evidence

A 2021 meta-analysis concluded fractional CO2 is an effective option for atrophic acne scars, and a 2024 meta-analysis (418 patients) found it outperforms Er:YAG fractional laser on effective response rate. A 2026 meta-analysis of 8 RCTs (249 patients) also found it superior to RF microneedling for scar improvement and satisfaction. Typical courses are 2 to 4 sessions 4 to 8 weeks apart, with improvement commonly in the 25 to 75 percent range depending on scar type.

Multiple randomized controlled trials or a meta-analysis support this use. The effect is real and repeatable.

The efficacy of fractional CO2 laser in acne scar treatment: A meta-analysis (Dermatologic Therapy, 2021; meta-analysis)
Efficacy and safety of CO2 fractional laser versus Er:YAG fractional laser in the treatment of atrophic acne scar: A meta-analysis and systematic review (Journal of Cosmetic Dermatology, 2024; meta-analysis)
Fractional CO2 Laser Versus Micro Needling Radiofrequency for Post Acne Scarring: A Meta-Analysis of RCTs (Journal of Cosmetic Dermatology, 2026; meta-analysis)

For wrinkles and fine lines

Moderate evidence

A comparative trial found both fractional CO2 and Er:YAG produce considerable improvement in facial wrinkles without serious adverse events, and a 2025 expert consensus supports it as a standard tool for facial photoaging. Most wrinkle data comes from split-face and comparative trials rather than large sham-controlled RCTs, which is hard to run for an ablative device, so the grade stays moderate despite consistent results.

Randomized trials support this use, but they are few, small, or short. The effect is probably real. The size of it is less certain.

Efficacy and safety of fractional CO2 laser versus fractional Er:YAG laser in the treatment of facial skin wrinkles (Lasers in Medical Science, 2017; clinical-trial)
Expert Consensus on Clinical Recommendations for Fractional Ablative CO2 Laser in Facial Skin Rejuvenation Treatment (Lasers in Surgery and Medicine, 2025; review)

For skin laxity

Limited evidence

Measurable skin tightening after fractional CO2 has been quantified with mechanical skin testing, and expert panels report using it off the face for mild laxity, but the tightening effect is modest and there are no large controlled trials showing it competes with surgical or even ultrasound-based lifting. Clinics selling CO2 as a laser facelift are overselling; it firms texture more than it lifts.

Only small, short, or lower-quality studies exist. Treat marketing claims about this use with caution.

Skin tightening induced by fractional CO2 laser treatment: quantified assessment of variations in mechanical properties of the skin (Journal of Cosmetic Dermatology, 2012; clinical-trial)
Expert Consensus on Clinical Recommendations for Fractional Ablative CO2 Laser in Facial Skin Rejuvenation Treatment (Lasers in Surgery and Medicine, 2025; review)

Risks and what can go wrong

The most downtime of common energy devices: 5 to 10 days of oozing, crusting, swelling, and redness, with residual pinkness for weeks to months. Common adverse events are transient erythema, edema, and post-inflammatory hyperpigmentation; rarer ones include infection, herpes reactivation (antiviral prophylaxis is standard), delayed hypopigmentation, and scarring. Pigmentation risk rises sharply in Fitzpatrick IV to VI, where many clinicians choose non-ablative or RF alternatives or use conservative settings. Avoid with active infection, recent isotretinoin per prescriber judgment, keloid history, or inability to do strict sun avoidance during healing.

The practical details

Often 1 to 3 sessions spaced 1 to 2 months apart; full results at 3 to 6 months. US pricing typically 1,000 to 2,500 dollars or more per full-face session. Strictly in-office, usually with topical or local anesthesia.