Intense pulsed light (IPL) therapy is a non-invasive skin treatment that uses broad-spectrum light to target pigmentation, visible blood vessels, unwanted hair, and signs of aging. Unlike a laser, which emits a single wavelength, an IPL device fires a flash of light containing green, yellow, red, and infrared wavelengths simultaneously. This allows it to treat multiple skin concerns in the same session, making it one of the more versatile light-based treatments in dermatology.
How IPL Works
IPL relies on a principle called selective photothermolysis. In plain terms, certain substances in your skin absorb specific wavelengths of light and convert that light into heat. These light-absorbing targets, called chromophores, include melanin (the pigment in dark spots and hair follicles), hemoglobin (the protein that gives blood its color), and water. When the IPL flash hits your skin, the light passes through the surface and is absorbed by whichever chromophore matches its wavelength range. The surrounding tissue is largely spared.
For pigmented spots like sun damage or freckles, melanin absorbs the light energy and heats up, breaking apart the pigment so your body can clear it away. For visible blood vessels and redness, hemoglobin absorbs the energy, heating the vessel wall until it coagulates and collapses. The body then replaces the damaged vessel with normal tissue over the following days. For hair removal, melanin in the hair follicle absorbs the light and converts it to heat, destroying the follicle’s ability to regrow hair.
Because the light contains multiple wavelengths at once, IPL can target different forms of hemoglobin as well. It reaches the type found in red lesions, the type in blue or purple veins, and everything in between. This polychromatic quality is what separates IPL from lasers, which hit only one target at a time.
What IPL Treats
The FDA has approved IPL for a broad list of skin conditions. The most common uses fall into three categories: pigmentation problems, vascular issues, and hair removal.
- Pigmented lesions: sun spots (solar lentigines), freckles, melasma, and general hyperpigmentation from sun damage.
- Vascular lesions: rosacea, spider veins on the face (telangiectasias), port-wine stains, hemangiomas, leg veins, and the red-brown discoloration on the neck and chest known as poikiloderma of Civatte.
- Hair removal: reduction of unwanted hair on the face and body.
- Photorejuvenation: overall improvement in skin texture, fine wrinkles, and uneven tone caused by years of sun exposure.
- Acne: IPL can reduce active acne by targeting bacteria and inflammation.
Beyond skin, IPL has gained attention for treating a common cause of dry eye called meibomian gland dysfunction, where the oil-producing glands in the eyelids become blocked. The theory is that IPL heats abnormal blood vessels around the eyelids, helps liquefy hardened oil secretions, and reduces bacterial growth. A meta-analysis of four randomized controlled trials found that IPL improved an objective measure of tear stability but did not significantly change patients’ subjective feeling of dryness. The evidence for this use is still developing.
How IPL Differs From Laser
The core difference is specificity. A laser produces a single, precise wavelength of light, while IPL produces a broad band of wavelengths filtered to a desired range. Think of a laser as a sniper and IPL as a shotgun with a tighter spread. Because lasers are more targeted, they can be more effective for a specific problem and may carry a lower risk of side effects for that particular condition. IPL’s advantage is versatility: a single device can address redness, brown spots, and skin texture in the same treatment.
In practice, dermatologists often choose between the two based on the condition being treated, the patient’s skin tone, and the level of precision needed. For someone with multiple overlapping concerns, like sun spots mixed with redness and uneven texture, IPL can address all of them at once.
What a Treatment Session Looks Like
A typical IPL session takes 20 to 30 minutes for the face. Your provider applies a cool gel to the treatment area, then presses the device’s handpiece against your skin and triggers a series of light pulses. Most people describe the sensation as a quick snap, similar to a rubber band flicking the skin. Some areas are more sensitive than others, but the discomfort is generally mild.
Afterward, expect a mild sunburn-like sensation that lasts anywhere from 2 to 24 hours, though it can occasionally persist up to 72 hours. Mild redness and swelling typically resolve within two to three days. Treated blood vessels gradually fade over 10 to 14 days. Dark spots often darken initially before flaking off over the following week or two.
Post-treatment care is straightforward: apply wrapped ice packs for 10 to 15 minutes periodically on the day of treatment, keep the skin moisturized, and avoid direct sun exposure. Sunscreen is essential during the healing period because treated skin is more vulnerable to UV damage.
How Many Sessions You’ll Need
Most dermatologists recommend starting with a series of three to six sessions spaced about four weeks apart. The exact number depends on the condition being treated and how your skin responds. Vascular lesions and pigmentation often show noticeable improvement after two or three sessions, while hair removal typically requires the full course or more because hair grows in cycles and IPL only affects follicles in the active growth phase.
After the initial series, maintenance treatments every 6 to 12 months help sustain results, particularly if you spend significant time in the sun. New sun damage and blood vessel changes accumulate over time, so periodic touch-ups keep the improvements from fading.
Skin Tone and Safety Considerations
IPL works best on lighter skin tones (Fitzpatrick skin types I through III). The reason is simple: melanin is one of the chromophores IPL targets. In darker skin, the epidermis contains more melanin, which competes with the intended target for light absorption. This raises the risk of burns, post-treatment darkening (hyperpigmentation), or lightening (hypopigmentation) of the surrounding skin.
People with Fitzpatrick skin types IV through VI, which includes many individuals of South Asian, Middle Eastern, Hispanic, and African descent, face a higher risk of pigmentary complications from IPL. This doesn’t mean treatment is impossible, but it requires careful parameter adjustments and an experienced provider. In many cases, certain laser types are a safer alternative for darker skin tones because their single wavelength can be chosen to minimize melanin absorption in the epidermis.
Other factors that increase risk include recent sun exposure or tanning, active skin infections, use of photosensitizing medications, and a history of keloid scarring. A recent tan is particularly problematic because it temporarily increases epidermal melanin, creating the same absorption problem seen in naturally darker skin.
At-Home IPL Devices
Consumer IPL devices for home use have become widely available, primarily marketed for hair removal. These devices operate at significantly lower energy levels than professional units. One early FDA-cleared home device, for example, had a maximum energy output of 5 joules per square centimeter, well below the range used in clinical settings. Professional devices can deliver several times that amount, which is why they produce faster and more dramatic results.
Home devices include built-in safety features that professional devices don’t need. They only fire when the handpiece is in full contact with the skin, preventing accidental light exposure. Protective eyewear isn’t required because the light is contained within the device. Skin cooling isn’t necessary because the lower energy output generates less heat.
These devices have received FDA clearance for permanent hair reduction, and they can produce real results over time. The trade-off is that you’ll need more sessions, results take longer to appear, and the devices are generally not powerful enough to treat vascular lesions or significant pigmentation. For anything beyond gradual hair reduction, professional treatment remains the more effective option.