The erbium laser emits light at 2,940 nanometres, a wavelength that water absorbs about ten times more strongly than the CO2 laser's wavelength. Your skin is mostly water, so that energy is used up almost entirely in the very thin layer it lands on. The tissue there is vaporised instantly and cleanly, and comparatively little heat spreads into the layers underneath.
That single fact drives every difference between erbium and CO2. Less spreading heat means less collateral damage, less swelling, faster healing, and less risk of the lasting redness or pigment change that follows a strong CO2 treatment. It also means less of the heat-driven collagen tightening that makes CO2 more powerful for deep wrinkles and heavy scarring. Precision and gentleness on one side, raw power on the other.
As the wound heals, new skin grows in from the surviving structures below, and the repair process lays down fresh collagen over the following months. The result is smoother texture and softened scars. For growths like seborrheic keratoses and sebaceous hyperplasia, the mechanism is simpler still — the laser shaves the growth away in fine layers under direct view, which is why the cosmetic result on the face can be very good.
Stop isotretinoin at least six months before. Providers are strict about this because of the scarring risk.
Start antiviral tablets if you get cold sores, or if the treatment covers the area around the mouth. Most providers prescribe them for everyone having full-face resurfacing, starting a day or two before.
Stop retinoids about a week before, and stop waxing the area.
Avoid sun and self-tanner for at least four weeks. Being tanned at your appointment raises the risk of pigment problems afterwards.
Ask about pre-treatment for pigment if you have brown or Black skin. Many dermatologists start a lightening cream such as hydroquinone a few weeks beforehand to lower the risk of dark patches, and this is a reasonable thing to bring up yourself.
Arrange your week. Take the time off, tell people you will not look presentable, and do not book this before a wedding, holiday or important meeting.
Buy your supplies in advance: plain petrolatum, gentle cleanser, clean gauze, cool packs, and a hat.
Stop smoking if you can. It slows wound healing measurably.
Come with clean skin and no makeup.
Numbing cream is applied about an hour beforehand, so arrive early. For full-face treatment you may be given a nerve block or sedation, in which case arrange a driver.
Numbing cream goes on and sits for 45 to 60 minutes. Full-face resurfacing usually also involves injected local anaesthetic or nerve blocks, and sometimes light sedation.
Your eyes are protected with metal shields or goggles — everyone in the room wears eye protection.
The provider passes the laser over the area. Each pass removes a thin layer, and they stop when they reach the depth they are aiming for. You will hear small popping or crackling sounds and smell burning — a smoke evacuator sits near your face for that reason.
With proper numbing, most people describe pressure, heat and a prickling rather than pain. It is more uncomfortable than a fractional non-ablative laser and less than most people fear.
Time depends on the area. A single growth takes a few minutes. A fractional treatment of the face takes 20 to 30 minutes. Full-face ablative resurfacing takes 30 to 60 minutes plus the numbing.
Afterwards the skin looks raw, pink or red and feels hot, like a bad sunburn. Ointment and sometimes dressings go on before you leave.
Day 1: burning and stinging like a strong sunburn, worst in the first several hours. The skin weeps clear fluid, and this is normal — keep it covered in plain petrolatum. Swelling begins. Cool packs and a couple of pillows help.
Day 2–3: peak swelling, usually on day two, and it can be dramatic on the face and around the eyes. Weeping continues, then starts to dry. This is the low point, and most people find it worse than they expected. Keep the skin moist at all times — crusting over a dry surface delays healing and raises the scarring risk.
Day 3–5: the surface starts to knit closed. Peeling and flaking begin. Do not pick, pull or exfoliate anything.
Day 5–7: most people are through the raw phase and have new, bright pink skin. This is when you can usually be seen in public and start wearing mineral makeup, once your provider says the skin is closed.
Weeks 2–6: pink fading to normal. Erbium leaves less prolonged redness than CO2, but expect several weeks of pinkness after a full treatment, longer on fair skin.
Throughout and afterwards: sun avoidance is non-negotiable, and daily sunscreen once the skin is closed. Sun exposure on healing skin causes the dark patches that people most regret. Fractional and spot treatments run the same course on a shorter timeline — usually two to four days.
The first two weeks look worse, not better. Judge nothing until the pink has settled.
At one month, texture and tone are visibly improved and most of the redness has gone.
The real result arrives between three and six months, as new collagen builds. Acne scars keep softening over that whole period, which is why a second session is not scheduled early.
For acne scars, expect a meaningful improvement rather than erasure. Shallow boxcar scars and general roughness respond best. Deep icepick scars do not respond well to any resurfacing laser and need a different approach. Two to four fractional sessions are typical, and a fully ablative session does more per treatment. Compared with CO2, erbium generally needs more sessions to reach the same place.
For growths — seborrheic keratoses, sebaceous hyperplasia, milia — removal is immediate and usually permanent for that growth. New ones can still form nearby, particularly with sebaceous hyperplasia, which tends to come back over a year or two.
Resurfacing results for texture and fine lines last years, but your skin keeps ageing and accumulating sun damage. Daily sunscreen is what determines how long you keep what you paid for.
There is no home version of an ablative laser, and there should not be. Removing the top layer of skin is a wound, and the difference between a good result and a scar is depth control by someone trained to judge it.
At-home fractional "laser" devices are much weaker non-ablative units. They can give a mild improvement in texture with months of consistent use. They will not do what an ablative session does, and marketing that compares the two directly is not being straight with you.
Home microneedling rollers and pens are a different treatment, not a cheaper version of this one. Used at needle depths that would actually match resurfacing, they cause scarring and infection at home.
What genuinely does help at home is unglamorous: a prescription retinoid used consistently for a year improves texture, fine lines and pigment, with good evidence behind it. Daily sunscreen prevents the damage that resurfacing is later paid for. Neither will remove a scar or a seborrheic keratosis — for those, the procedure is the procedure.