Acne can settle down and still leave a record of itself in the skin. For some people that record is a change in colour that fades over months. For others it is a change in texture that does not fade, because the skin healed with less collagen than it started with. Those indentations are what people mean when they talk about acne scarring, and they are the reason resurfacing treatments exist.
CO2 laser resurfacing is one of the treatments used for textured acne scarring. It is also one of the more involved ones, with real downtime attached, so it is worth understanding what it does before deciding whether it is the right choice for your skin.
Marks and scars are not the same thing
The first thing worth separating is colour from texture, because they respond to completely different treatments.
Flat brown or red patches left behind after a spot clears are pigment and blood vessel changes rather than scars. Brown marks are usually described as post-inflammatory hyperpigmentation and red marks as post-inflammatory erythema. They sit level with the surrounding skin, and many fade over time or respond to treatments aimed at pigment and redness rather than texture.
True acne scars change the surface of the skin. Run a finger over them and you feel a dip. Under strong light from the side they cast small shadows, which is why scarring often looks worse in a lift or a bathroom mirror than it does in daylight. Those dips are collagen loss, and the only way to improve them is to prompt the skin to build new collagen in the right place.
The three common shapes
- Ice pick scars are narrow and deep, like a small puncture. They are the most stubborn of the three.
- Boxcar scars are wider with defined edges, a little like a shallow crater.
- Rolling scars are broad and soft-edged, giving skin an uneven, undulating look.
Most people have a mixture, which is why an assessment matters more than a treatment name. The shape of the scarring tends to decide the approach.
What CO2 laser resurfacing actually does
A CO2 laser emits light at a wavelength that water absorbs strongly. Skin is largely water, so the energy is taken up in the surface layers rather than passing deeper. In practical terms the laser removes tissue in a very controlled way and heats the layer beneath it, and the skin responds by producing new collagen as it heals.
Modern treatment is usually fractional. Rather than treating the whole surface at once, the laser delivers energy in a grid of microscopic columns, leaving untreated skin in between. That untouched skin acts as a reservoir for healing, which is what allows a treatment this intensive to recover in days rather than weeks.
The visible improvement is not immediate. Resurfacing sets off a remodelling process that continues for weeks and months afterwards, so the skin generally keeps improving well after the surface has healed. Results vary from person to person.
Which acne scars respond best
CO2 resurfacing works by smoothing the transition between scarred and unscarred skin, so it tends to do most for scars with a shape it can soften. Rolling and boxcar scars usually fall into that group.
Ice pick scars are a different problem. They are narrow and deep, and resurfacing the surface does not reach the base of them, so they often need a technique that treats the individual scar before or alongside resurfacing. That is a decision for the doctor assessing your skin, not something to plan in advance from a website.
This is also why scarring is rarely treated with one method alone. A plan might combine resurfacing with other approaches to acne scarring for the scars that will not respond to it.
Who it suits, and who it does not
CO2 resurfacing is a medical treatment, and suitability is assessed individually. Several things need discussing at consultation:
- Active acne. Scarring is usually treated once the acne itself is under control, because treating skin that is still breaking out can mean treating a moving target.
- Skin tone. Ablative resurfacing carries a higher risk of pigment change in richer skin tones, so the assessment covers whether CO2 is the right choice or whether another approach suits your skin better.
- Recent medication. If you have taken oral acne medication, the timing of any resurfacing needs to be discussed with the doctor.
- A history of keloid or raised scarring, or of cold sores, both of which change how a treatment is planned.
- Recent sun exposure or a tan, which usually means waiting.
- Pregnancy or breastfeeding.
None of this rules anybody out on its own. It is the reason the consultation and patch test come first rather than the treatment.
What to expect on the day
Treatment is preceded by a consultation and a patch test. On the day, numbing cream is applied and left to work before treatment starts. Most people describe the sensation as hot and prickling rather than sharp, with cool air used through the session for comfort.
At Pulse Light Clinic, CO2 resurfacing is carried out on the full face and above. It is not offered as a partial-area treatment.
Immediately afterwards the skin looks and feels as though it has caught the sun: red, warm and tight, sometimes with mild swelling for the first day or two. Over the following days the surface takes on a fine sandpaper texture and a bronzed look before flaking away, which is the treated tissue clearing. Picking at it is the one thing to avoid.
Plan for social downtime rather than time off your feet. Most people prefer to keep the first several days free of anything where they would rather not be visibly healing, and makeup is generally reintroduced only once the skin has settled. Aftercare is straightforward and centres on keeping the skin clean, well moisturised and protected from sun, and daily sun protection matters for weeks afterwards, not days.
How many sessions and when you see change
The number of sessions depends on the depth and extent of the scarring, and is agreed at consultation rather than sold as a fixed package. Improvement builds gradually as collagen remodels, so the skin at three months usually looks different from the skin at three weeks. Results may vary, and scarring is improved rather than erased.
Where CO2 sits alongside other treatments
CO2 is one option among several, and the useful question is which tool suits which problem rather than which is strongest.
- Fraxel is a fractional laser often considered where a gentler resurfacing profile is preferred.
- Morpheus8 combines microneedling with radiofrequency energy, working through the skin rather than removing the surface, and is often discussed for rolling scarring alongside laxity.
- Dermapen microneedling is a lighter option that stimulates collagen without ablation.
- LaseMD and IPL are aimed at the colour side of the problem, the brown and red marks rather than the dips.
A good plan often uses more than one of these in sequence. What matters is that the choice follows an assessment of your particular scarring, not a general ranking of devices.
Why the consultation comes first
Acne scarring is one of the areas where the assessment does more work than the device. The same face can carry three different scar types, each responding to something different, and skin tone, medication history and how recently the acne settled all change the plan.
Pulse Light Clinic is CQC-registered and doctor-and-nurse-led, and has been treating skin in London since 2001. A consultation covers what your scarring is, what can realistically be improved, and which treatment or combination of treatments suits your skin.
Book a consultation to have your skin assessed and a plan explained before any treatment is booked.
