Laser treatment is any medical or cosmetic procedure that uses a focused beam of light to cut, heat, or destroy targeted tissue in the body. The word “laser” stands for Light Amplification by Stimulated Emission of Radiation. What makes it useful in medicine is precision: different wavelengths of light interact with different colors and structures in your body, allowing a laser to treat one type of tissue while leaving surrounding tissue largely unharmed.
How Lasers Target Specific Tissue
The core principle behind most laser treatments is called selective photothermolysis. In plain terms, the laser emits a specific color of light that gets absorbed by a specific target in your body, converting that light energy into heat. The target might be the red pigment in blood vessels, the brown pigment in a birthmark, or the dark ink in a tattoo. Because the surrounding tissue doesn’t absorb that particular wavelength as strongly, it stays relatively cool and undamaged.
A laser tuned to 577 nanometers, for instance, is absorbed strongly by hemoglobin (the pigment in red blood cells) but passes through melanin in the skin with much less absorption. That’s why it can treat visible blood vessels or port-wine stain birthmarks without destroying the skin above them. Similarly, lasers designed for pigmented lesions deliver very short pulses of energy that confine heat to the tiny granules of melanin inside pigment cells, breaking them apart so the body can clear them away.
Common Uses in Dermatology
Skin treatments are where most people encounter lasers. Over the past 40 years, laser technology has expanded from treating birthmarks to addressing wrinkles, scars, tattoos, unwanted hair, sun damage, freckles, and visible blood vessels on the face. The treatments fall into two broad categories.
Ablative lasers remove the outer layer of skin and heat the tissue underneath, triggering the body to produce new collagen as it heals. The result is smoother, tighter skin. Recovery is more involved: new skin typically covers the treated area in 7 to 10 days, but full recovery takes at least a month. With a CO2 laser, expect roughly two weeks of downtime. Erbium lasers heal a bit faster, usually within one full week. During recovery, the skin may be raw, oozing, or blistered, similar to a severe sunburn.
Non-ablative lasers also stimulate collagen growth but without destroying the outer skin layer. Recovery is measured in hours rather than weeks. You might have some swelling or temporary color changes, but most people return to normal activities the same day. The tradeoff is that results are subtler and more gradual, typically requiring 2 to 4 sessions spaced over weeks or months before changes become noticeable. You’re more likely to see improvements in skin texture and tone than dramatic wrinkle reduction.
Both types can be used in a fractional mode, where the laser creates microscopic columns of treated tissue rather than treating the entire surface. This speeds healing while still delivering results.
Laser Vision Correction
Laser eye surgery reshapes the cornea to correct how light focuses on the retina. Three main procedures exist. LASIK treats nearsightedness, farsightedness, and astigmatism by creating a thin flap in the cornea, reshaping the tissue underneath with a laser, then replacing the flap. PRK treats the same three conditions but removes the outer layer of the cornea entirely before reshaping, which means a longer recovery but avoids flap-related complications. SMILE is a newer approach that corrects nearsightedness and astigmatism through a small incision, without creating a flap, though it cannot yet treat farsightedness.
Treating Tumors and Precancerous Tissue
Lasers have been used in cancer treatment since the 1980s, when early clinical testing began on brain, liver, pancreatic, and prostate tumors. Laser ablation works by inserting a thin fiber into or near a tumor and delivering enough heat to destroy cancer cells while sparing surrounding healthy tissue. It’s gaining acceptance as an alternative to traditional surgery for certain tumors, particularly when the goal is a less invasive approach.
The choice of laser depends on the tumor’s location. Lasers with wavelengths that tissue absorbs strongly work for surface-level treatment. For deeper tumors, wavelengths that penetrate further into tissue are needed. Treatments can run from a few minutes to more than 20 minutes in continuous mode, using relatively low power to gradually heat the target area.
Vascular and Pigmented Lesions
For visible blood vessel problems like port-wine stains, spider veins on the face, and certain types of hemangiomas, the pulsed dye laser is considered the treatment of choice because of its effectiveness and low risk of scarring. Older continuous-wave lasers like argon caused more non-specific tissue damage and have largely been replaced.
For pigmented lesions, short-pulse lasers (including picosecond lasers) can lighten or eliminate freckles, certain birthmarks, and tattoos. These systems deliver energy in incredibly brief bursts that shatter pigment particles without heating surrounding tissue enough to cause scarring. Tattoo removal typically requires multiple sessions because each treatment breaks down a portion of the ink, which the body then gradually clears.
What to Expect Before Treatment
Preparation varies by procedure, but several guidelines apply broadly. You’ll typically need to avoid sun exposure and tanning beds for at least two weeks beforehand, since tanned skin absorbs more laser energy and increases the risk of burns or discoloration. Certain medications also create problems. Antibiotics in the tetracycline or fluoroquinolone families make skin more sensitive to light and should be finished at least two weeks before treatment. Isotretinoin (a strong acne medication) requires a six-month waiting period. Blood thinners, including aspirin at doses above 81 mg, should generally be stopped two weeks prior. Immunosuppressant medications require a six-month gap as well.
Topical skincare products with active ingredients, including retinoids, chemical exfoliants, and benzoyl peroxide, usually need to be paused for one to two weeks. Some herbal supplements, particularly St. John’s Wort, can increase light sensitivity and should also be avoided. If you’re pregnant or breastfeeding, most laser procedures are off the table.
Recovery and Side Effects
For most cosmetic laser treatments, the immediate sensation is similar to a mild sunburn: redness, swelling, and possibly some stinging or itching for a few days. More aggressive ablative treatments can leave skin raw and oozing, sometimes with blistering and a yellowish crust as the area heals. Around five to seven days post-treatment, the skin typically becomes dry and begins to peel.
Once healed, new skin will appear pink. This color gradually fades over two to three months, though it can take up to a year for pinkness to fully resolve. Sun protection becomes essential after any laser procedure, since the fresh skin is highly vulnerable to UV damage and discoloration.
Cost Considerations
The average cost of laser skin resurfacing is around $1,829, according to the American Society of Plastic Surgeons. That figure varies significantly based on the type of laser used, the size of the treatment area, the provider’s expertise, and geographic location. Additional costs may include facility fees, anesthesia, and post-procedure medications. Most cosmetic laser treatments are not covered by insurance. Medical applications, such as treating precancerous lesions or certain vascular conditions, are more likely to be covered, though policies vary.
FDA Safety Classifications
The FDA classifies lasers into four hazard classes, from Class I (considered non-hazardous) to Class IV (capable of causing immediate skin and eye injury from direct or even reflected beams). Consumer laser products generally fall into the lower classes, while medical lasers used for surgery and treatment are typically Class IIIb or IV. These higher-class devices require trained professionals, protective eyewear, and controlled treatment environments. The labeling on any Class II through IV laser must include a warning symbol stating its class and output power.