Laser Treatment for Scars: When to Start? How Many Sessions? Can Children Have It?

After an injury, a burn, or surgery, many people worry about being left with a noticeable scar. You may expect the scar to fade gradually once the wound has healed, only to find it turning red and raised, or becoming itchy, painful, or tight. At this point, people often ask: "How long do I need to wait before a scar can be treated with a laser?" "Can laser treatment make a scar disappear completely?" "Is laser treatment suitable for children?"

With advances in medical technology, laser treatment has become one of the important options for treating scars. Besides improving appearance, it may also relieve the discomfort that scars cause, and may even improve some scar contractures.

Why Do Wounds Leave Scars After Healing?

Any wound can leave a scar. How severe a scar becomes depends on the depth of the injury, how long the wound takes to heal, and each person's constitution, among other factors. When the deeper layers of the skin are injured, for example by a burn, trauma, or a surgical incision, the body produces collagen to repair the damaged tissue. The deeper the injury and the longer it takes to heal, the more severe the scar may become.

A scar does not stay the same once the wound has healed; it goes through a maturation process that lasts from several months to more than a year. During this time, the scar may gradually become red, thicker, and harder, and may also become itchy, painful, or tight. Some severe scars may even cause the skin to contract, limiting joint movement.

How Soon After a Wound Heals Can Laser Treatment Begin?

It used to be commonly believed that a scar had to wait six months to a year, until it was fully mature, before it could be treated with a laser. However, recent studies have found that for some scars, laser treatment started early after the wound has healed may help reduce scar overgrowth and improve the scar's later appearance.

In general, once the wound has completely healed, with no broken skin, oozing, or infection, a doctor can assess whether laser treatment can begin; laser treatment can usually be considered about 3–6 months after the wound has healed.

Is Earlier Always Better?

Early treatment may help, but earlier is not always better.

A scar keeps changing after the wound has healed. Burn scars in particular may gradually thicken and harden over several months. Appropriate early laser treatment may help reduce scar overgrowth.[1]

However, if the wound has not fully healed, is still infected, or the skin is too fragile, the skin can easily break open again, and treating too early may instead cause new damage.

So what matters is not how many days after healing the laser is started, but the doctor's assessment of whether the wound is stable, how the scar is changing, and which type of laser is suitable.

What Types of Scar Lasers Are There?

The scar lasers in common use today mainly include the following two types:

Pulsed Dye Laser (PDL)

Mainly improves: scar redness and increased blood vessels.

This type of laser acts mainly on the blood vessels in the scar. It can improve scar redness and may also relieve some itching and early scar overgrowth.

It is particularly suited to scars that remain noticeably red after the wound has healed.

Fractional CO₂ Laser

Mainly improves: scar thickening, stiffness, uneven surface, and tightness.

The fractional CO₂ laser creates many tiny treatment zones within the scar tissue, encouraging the collagen to rearrange and the tissue to remodel.

For hypertrophic scars after burns, it may help improve scar thickness, softness, and skin texture, and may also relieve itching, pain, and some skin tightness.[2,3]

If a scar is red, thick, and stiff at the same time, the doctor may also arrange different lasers in separate sessions or in combination.

How Many Sessions Are Needed?

Scar laser treatment is usually not completed in a single session.

Generally, about 3–5 or more sessions may be needed; the actual number still depends on the severity and extent of the scar and how it responds to treatment.

Typical treatment intervals are about once every 4–8 weeks.[2,3,4]

After treatment, scars may gradually become flatter and softer, and their color or surface texture may also improve.

It is important to note that the goal of laser treatment is to improve the scar, not to make it disappear completely, and results vary with each person's constitution and the characteristics of the scar.

Can Children Have Scar Laser Treatment?

Yes. Being a child is not a contraindication to scar laser treatment.

Children are still growing and developing. If a scar from a burn or other injury keeps thickening or contracting, it may affect joint movement and normal development. A pediatric scar treatment guideline published in 2025 states that some children can be assessed for early laser treatment within a few weeks after the wound has completely healed.[4] However, not every child needs laser treatment. The doctor will decide whether treatment is needed based on the child's age, the location and severity of the scar, and how well the child can cooperate with treatment.

A topical anesthetic cream can be used during treatment to reduce pain; if the child is young, the treatment area is large, or the child has difficulty cooperating, sedation or general anesthesia may need to be considered.

What Should I Watch for After Laser Treatment?

Reactions after treatment differ between the two lasers.

After pulsed dye laser treatment, there may be temporary redness and swelling or bruising. Fractional CO₂ laser treatment may leave tiny wounds, scabbing, or flaking; the skin surface usually takes several days to about a week to recover, while redness may last longer.

After treatment, keep the skin moisturized and protected from the sun, care for the treated area as instructed by your doctor, and avoid picking off the scabs. A small number of patients may develop hyperpigmentation, infection, or worsening of the scar.

In addition, scar treatment does not rely on laser alone; some patients still need to combine it with silicone gel, pressure garments, medication injections, or rehabilitation therapy to achieve better results.

Conclusion

Scar laser treatment does more than improve appearance; it may also help relieve itching, pain, and tightness.

A scar does not have to be fully mature before treatment begins, but earlier is not always better. With a professional assessment and the right choice of treatment timing and laser type, scars can be improved safely. If, after the wound has healed, the scar stays red, raised, or itchy, or limits your movement, it is advisable to have it evaluated early at a plastic surgery or scar clinic.

References

1. Seago M, Shumaker PR, Spring LK, et al. Laser Treatment of Traumatic Scars and Contractures: 2020 International Consensus Recommendations. Lasers in Surgery and Medicine. 2020;52(2):96–116. DOI: 10.1002/lsm.23201
2. Douglas H, Lynch J, Harms KA, et al. Carbon dioxide laser treatment in burn-related scarring: A prospective randomised controlled trial. Journal of Plastic, Reconstructive & Aesthetic Surgery. 2019;72(6):863–870. DOI: 10.1016/j.bjps.2019.01.027
3. Lewis CJ, Douglas H, Martin L, et al. Carbon dioxide laser treatment of burn-related scarring: Results of the ELIPSE (Early Laser Intervention Promotes Scar Evolution) prospective randomized controlled trial. Journal of Plastic, Reconstructive & Aesthetic Surgery. 2023;84:368–376. DOI: 10.1016/j.bjps.2023.06.012
4. Chinese Burn Association. Clinical practice guideline for pediatric scar prevention and treatment (2025 edition). Burns & Trauma. 2025;13. DOI: 10.1093/burnst/tkaf065

This article provides general health information and does not replace individual medical advice. Actual treatment must be decided after an in-person evaluation.