Lasers in Dermatology Explained: Intense Pulsed Light, Vascular, Pigment and Ablative Treatments
Laser and light-based treatments can soften redness, fade unwanted pigment, improve scars, reduce hair growth and resurface damaged skin. They can also cause burns, pigment changes or scarring when the wrong device is used on the wrong skin type. The difference often comes down to careful diagnosis, correct laser selection and realistic expectations.
Modern dermatology uses several kinds of energy devices. Some target blood vessels. Others target melanin, tattoo ink, water in the skin or the hair follicle. Some remove the skin surface in a controlled way, while others heat deeper layers without breaking the surface.
This guide explains how the main laser and light treatments work, what they can treat, and what recovery usually looks like. It is for general information only and does not replace assessment by a qualified dermatologist or appropriately trained clinician. If considring a laser treatment, please see an appropriate qualified specialist,
How dermatology lasers work
A laser produces a focused beam of light at a specific wavelength. Different wavelengths are absorbed by different targets in the skin. Dermatologists call these targets chromophores. The main ones are:
Haemoglobin, found in blood vessels
Melanin, found in pigment and hair follicles
Water, found throughout skin tissue
Tattoo pigment, which can absorb certain laser wavelengths
The aim is to heat or fragment the chosen target while sparing the surrounding skin as much as possible. This principle is called selective photothermolysis. In simpler terms, the device is chosen so the unwanted structure absorbs more energy than nearby tissue.
Several treatment settings affect the result:
Wavelength
Determines what the light targets and how deeply it travels.
Fluence
The amount of energy delivered.
Pulse duration
How long each burst lasts.
Spot size
The size of the beam on the skin.
Cooling
Protects the skin surface and improves comfort.
Skin tone matters. Melanin in the outer skin can compete with the treatment target, especially in medium to dark skin tones or recently tanned skin. That is why experienced assessment and test spots may be needed before treatment.
IPL treats colour change across wider areas
Intense Pulsed Light, often called IPL, is not technically a laser. It uses broad-spectrum light filtered to target certain colours in the skin. Because it delivers a range of wavelengths rather than one precise wavelength, it can treat several concerns at once, but it is less specific than many true lasers.
IPL is commonly used for:
Sun-related pigmentation, such as freckles and lentigines
Diffuse redness and facial flushing
Mild visible blood vessels
Rosacea-related redness in suitable cases
Hair reduction
General photoageing, including uneven tone and texture
IPL tends to work best when there is a clear contrast between the target and surrounding skin. For example, dark hair against lighter skin usually responds better than blonde, grey or red hair. Brown spots caused by sun damage may darken at first, then flake away over several days.
Benefits of IPL include broad coverage, short treatment sessions and limited downtime for many patients. It can improve several signs of sun damage in one plan. It is often used on the face, neck, chest and hands.
Risks include temporary redness, swelling, blistering, burns, post-inflammatory hyperpigmentation and, less often, hypopigmentation. IPL can worsen melasma in some cases, especially if it triggers pigment activity. It is usually avoided on freshly tanned skin.
Recovery time is often short. Redness and warmth may settle within a few hours to a couple of days. Pigmented spots may darken and shed over 5 to 10 days. Hair reduction sessions usually have little visible downtime, although follicles can look red and bumpy briefly.
A course of treatments is usually needed. The exact number depends on the condition, skin type, device and response.
Vascular lasers target redness and visible vessels
Vascular lasers are designed to treat blood vessels by targeting haemoglobin. They heat unwanted vessels so the body can gradually clear them or reduce their appearance.
Common vascular lasers include pulsed dye lasers and certain Nd:YAG lasers. Different devices suit different vessel sizes and depths. A fine red facial capillary is not the same as a deeper blue leg vein, so device choice matters.
Vascular lasers may treat:
Facial thread veins
Rosacea-related visible vessels
Port-wine stains
Cherry angiomas
Spider naevi
Some scars with persistent redness
Certain vascular birthmarks
Bruising or redness after procedures, where appropriate
For rosacea, vascular lasers can reduce visible vessels and background redness. They do not cure rosacea, so ongoing trigger management and skincare may still be needed. For port-wine stains, treatment often requires multiple sessions and results vary by location, depth and age of the lesion.
Benefits of vascular lasers include precise targeting of red and purple vessels, strong results for selected vascular lesions and the option to treat small areas accurately. They can also improve the red phase of scars, which can be distressing even when texture has settled.
Risks include temporary swelling, redness, bruising, crusting and pigment changes. Pulsed dye laser treatment can produce purpura, which looks like purple bruising, when settings are chosen for stronger vessel clearance. Rare risks include blistering, scarring and textural change.
Recovery time depends on the device and settings. Mild redness may settle in 24 to 48 hours. Swelling, especially around the eyes, can last a few days. Bruising-type purpura may take 7 to 14 days to fade. Sun protection is essential while the skin recovers.
Pigment lasers break up excess melanin and tattoo ink
Pigment lasers target melanin or artificial pigment. They often use very short pulses to shatter pigment into smaller particles. The body then clears some of that debris over time.
Devices used for pigment include Q-switched and picosecond lasers. Picosecond lasers deliver energy in extremely short pulses. They are often used for tattoos and selected pigment concerns, although the best choice still depends on the pigment type, colour, depth and skin tone.
Pigment lasers may treat:
Solar lentigines, often called sun spots
Freckles in selected cases
Naevi of Ota and other dermal pigment conditions
Some birthmarks
Certain types of post-inflammatory pigmentation
Tattoos, including professional and amateur tattoos
Pigment concerns need accurate diagnosis. A brown mark should not be treated with a laser until a clinician has ruled out suspicious lesions. Lasering an undiagnosed skin cancer can delay proper diagnosis and care.
Melasma needs special caution. It is a complex pigment condition influenced by hormones, genetics, sun exposure and heat. Some laser treatments can worsen it. For many people, topical treatment and strict sun protection form the foundation of care, with light or laser considered only in selected cases.
Benefits of pigment lasers include precise treatment of discrete brown spots, potential fading of difficult dermal pigment and effective tattoo lightening over a series of sessions. They can target pigment without removing the skin surface when used correctly.
Risks include darkening or lightening of the skin, blistering, crusting, incomplete clearance, colour change in tattoos and scarring. People with darker skin tones may have a higher risk of pigment change because epidermal melanin can absorb some of the energy.
Recovery time varies. Treated brown spots often darken, crust lightly and flake over 5 to 10 days. Tattoo treatment can cause whitening, redness, swelling, pinpoint bleeding or blistering, with surface healing often taking 1 to 2 weeks. Tattoo fading continues gradually between sessions.
Ablative and non-ablative lasers resurface or remodel skin
Resurfacing lasers mainly target water in the skin. They treat texture, wrinkles, scars and sun damage by removing or heating controlled zones of tissue. This stimulates wound healing and collagen remodelling.
The key distinction is whether the laser removes the skin surface.
Ablative lasers remove controlled layers of skin
Ablative lasers vaporise thin layers of skin. Common examples include carbon dioxide lasers and erbium:YAG lasers. They can treat deeper lines and more marked textural change than many non-ablative devices, but they involve more downtime and higher aftercare needs.
Ablative lasers may treat:
Acne scars
Surgical and traumatic scars
Fine lines and wrinkles
Sun-damaged skin
Actinic keratoses in selected treatment plans
Enlarged pores and rough texture
Certain benign skin growths, when medically appropriate
Ablative treatments can be fully ablative or fractional. Fractional treatment creates microscopic treatment zones while leaving surrounding skin intact. This usually speeds healing compared with fully ablative resurfacing.
Benefits of ablative lasers include strong improvement in texture, scars and wrinkles after fewer sessions than gentler options. They can produce visible resurfacing because they renew the skin surface and trigger deeper repair.
Risks include infection, prolonged redness, acne flares, milia, pigment changes, scarring and delayed healing. Cold sore reactivation can occur in people prone to herpes simplex, so antiviral medicine may be recommended before facial treatment.
Recovery time depends on intensity. Light fractional ablative treatment may involve 5 to 7 days of visible healing. More intensive resurfacing can require 1 to 2 weeks for the surface to heal, with redness lasting several weeks or longer. Careful wound care and sun avoidance are central to recovery.
Non-ablative lasers heat the skin without removing the surface
Non-ablative lasers heat deeper skin layers while leaving the outer surface largely intact. They aim to stimulate collagen and improve tone or texture with less downtime than ablative treatment.
Non-ablative lasers may treat:
Mild acne scarring
Early fine lines
Enlarged pores
Mild texture irregularity
Redness with certain devices
Pigment concerns with selected devices
Hair reduction with appropriate wavelengths
Because the skin surface is not removed, results are usually more gradual. Several sessions are often needed.
Benefits of non-ablative lasers include lower downtime, lower wound-care demands and suitability for people who cannot take a long recovery period. They can be a good choice for gradual collagen remodelling.
Risks include temporary redness, swelling, discomfort, acne flare, pigment change and rare blistering or scarring. Results may be modest compared with ablative resurfacing, especially for deep scars or advanced sun damage.
Recovery time is usually short. Redness and swelling may settle within hours to a few days, occasionally longer. Fractional non-ablative treatments can produce a bronzed or sandpaper-like texture for several days.
Comparing common dermatology laser and light treatments
Treatment type | Main target | Common uses | Main benefits | Key risks | Typical recovery |
IPL | Melanin, haemoglobin and hair follicles, depending on filters | Sun spots, redness, hair reduction, uneven tone | Treats wider areas and several concerns in one plan | Burns, blistering, pigment change, melasma flare | Hours to a few days, with pigment flaking over 5 to 10 days |
Vascular lasers | Haemoglobin in blood vessels | Thread veins, rosacea vessels, port-wine stains, cherry angiomas and red scars | Precise treatment of red or purple vessels | Bruising, swelling, crusting, pigment change | 1 to 3 days for mild redness, up to 2 weeks if bruising occurs |
Pigment lasers | Melanin or tattoo ink | Sun spots, dermal pigment, tattoos, selected birthmarks | Breaks pigment into particles for gradual clearing | Increased or reduced pigmentation, blistering, incomplete clearance | 5 to 14 days for surface recovery, fading continues between sessions |
Ablative lasers | Water in skin tissue | Scars, wrinkles, sun damage, texture change | Strong resurfacing and collagen stimulation | Infection, prolonged redness, scarring, pigment change | Around 1 to 2 weeks for visible healing, redness can last longer |
Non-ablative lasers | Water, pigment, vessels or follicles, depending on device | Mild scars, early lines, texture, redness, hair reduction | Less downtime and gradual remodelling | Swelling, pigment change, blistering | Hours to several days |
These categories can overlap. For example, some non-ablative lasers target pigment, while others target water or vessels. A treatment plan may also combine devices over time.
Choosing the right treatment starts with diagnosis
The best device is not simply the newest one. It is the one that matches the diagnosis, skin type, treatment area, medical history and recovery window.
A safe consultation should cover:
The exact condition being treated
Natural skin tone and tanning history
History of keloid or hypertrophic scarring
Current medicines
Pregnancy or breastfeeding status
Cold sore history
Previous laser treatments and reactions
Recent sun exposure or fake tan
Expectations, budget and downtime
For darker skin tones, device choice and settings need particular care. Longer wavelengths may be safer for some indications because they can bypass more surface pigment, but this is not a rule for every condition. Conservative settings, test patches and longer intervals may reduce risk.
Pre-treatment preparation often includes daily broad-spectrum sunscreen, avoiding tanning, pausing irritating skincare actives and following specific instructions about hair removal or shaving. After treatment, most plans focus on cooling, gentle cleansing, moisturising, sun protection and avoiding heat exposure for a short period.
Benefits are strongest when expectations are realistic
Laser and light treatments can produce meaningful change, but they rarely create perfect skin. They work with biology, which means response varies.
Good candidates understand that:
Several sessions may be needed.
Maintenance can be necessary for chronic conditions such as rosacea.
Pigment can return with sun exposure.
Scars may improve rather than disappear.
Tattoo removal often takes many sessions and some colours are harder to treat.
Downtime may be longer than expected after strong resurfacing.
The most satisfying outcomes usually come from a plan that combines the right device with medical skincare, sun protection and enough healing time between sessions.
The safest route is a proper skin diagnosis, a device chosen for the specific concern, honest discussion of risks and careful aftercare. When those pieces are in place, laser and light treatments can be highly useful tools in modern dermatology.
