Taula de Continguts
The Q-Switched laser is a nanosecond-pulse laser that acts on the skin's pigment, and its 1064 nm wavelength reaches deeper than others, which is why it is also used for pigment located in the dermis. At Santé Madrid we work with the Q-Switched head of the Harmony XL Pro platform, and the medical team decides whether it is indicated, with which settings and how many sessions, always after assessing your skin. In this guide we explain how it works, how deep pigment differs from superficial spots, what is known about so-called dull tone, what sessions and aftercare involve, and who should wait.
Key points
- The Harmony XL Pro Q-Switched head is a 1064 nm Nd:YAG laser with nanosecond pulses; according to the manufacturer, a 532 nm tip targets superficial pigmentation.
- Not all pigment sits at the same depth: dermal pigment usually looks bluish brown or grey and usually needs several sessions spaced months apart.
- So-called laser toning, with low energy and repeated sessions, has been studied mainly in melasma; for dull tone in general the evidence is still limited.
- The main risks are post-inflammatory hyperpigmentation, more frequent in darker phototypes, and light patches if too much energy accumulates.
- Treatment is performed by the medical team after an assessment, and results vary from skin to skin.
How the Q-Switched head acts on pigment
The term Q-Switched describes a way of emitting light: the laser builds up energy and releases it in very short pulses, in the nanosecond range. On the official Harmony XL Pro page, Alma Lasers describes its Q-Switched head as a 1064 nm laser with a range of spot sizes and intense nanosecond pulses to treat pigmentation, and adds a 532 nm tip aimed at superficial pigmentation. The manufacturer indicates the platform for skin types I to VI depending on the specific treatment, which does not mean every head is used the same way on every skin.
A letter on lasers for lentigines published in the Journal of Cutaneous and Aesthetic Surgery explains that Q-Switched lasers emit high-energy radiation in nanoseconds and produce both a thermal and a mechanical effect on pigment. The basis is selective photothermolysis: if the pulse is short enough, the energy is concentrated in the target, in this case the melanin granules, and less heat passes to the surrounding tissue.
The same text notes that the 532 nm wavelength has limited penetration, about 250 μm, which is why it suits superficial lesions. If you want to see the other heads of the device and what each is used for, we explain it in our guide to the Harmony XL Pro laser in Madrid.
Superficial pigment and deep pigment: why depth matters
A spot can be caused by melanin built up in the epidermis, the outermost layer, or by pigment and pigmented cells lying further down, in the dermis. That difference changes almost everything: the colour you see, the wavelength that makes sense, the number of sessions and the risk. One example of dermal pigment is the bilateral nevus of Ota-like macules that appear in adulthood. A retrospective study of 110 patients published in Skin Research and Technology describes them as brown, blue-brown or slate-grey patches on both cheekbones, with pigmented cells in the mid and upper dermis.
The authors explain that they chose the 1064 nm Q-Switched Nd:YAG because it reaches deeper tissue and is poorly absorbed by epidermal melanin, which makes it relatively safe in darker skin. A review of dermal melanocytosis published in the Journal of Cosmetic Dermatology agrees that 1064 nm penetrates further and better protects the surface, although it notes that in lighter skin melanin absorbs it less, which may reduce its efficacy. The table gives an approximate summary of the differences.
| Aspect | Superficial pigment (epidermis) | Deep pigment (dermis) |
|---|---|---|
| Usual appearance | Brown | Bluish brown, grey or slate grey |
| Wavelength usually considered | 532 nm or other options for superficial lesions | 1064 nm, which penetrates further |
| Session rhythm | Depends on the type of spot and the assessment | Several sessions spaced months apart |
| What to watch for | Post-inflammatory hyperpigmentation | Post-inflammatory hyperpigmentation and slow response |
Working out where the pigment sits is the doctor's job. Typical sun spots have their own approach, which you can read about on our pigmentation laser page.
Dull tone and laser toning: what the studies say
As well as treating specific spots, the 1064 nm Q-Switched Nd:YAG is used with low energy, a large spot and repeated sessions, a technique the literature calls laser toning. A systematic review published in Medicina studies it in melasma and describes it as a generally effective and safe option. It explains that it acts on melanosomes, the tiny melanin deposits, without destroying the cells that make them, and that in studies it is usually applied every 1 or 2 weeks. Even so, it reports frequent relapses and cases of persistent light patches. If your case is melasma, it needs a plan of its own, which we summarise on our melasma laser page.
And what about skin that simply looks dull or uneven in tone? Here the evidence is thinner. A pilot study published in the Journal of Clinical Medicine treated 13 women with skin types II to VI with 7 full-face sessions every 2 weeks, and observed improvement in tone and texture and a fall in the melanin index. The data have clear limits: a small sample, no control group and dropouts during follow-up. That is why we present it as an option the doctor may consider, not as a proven solution for any dull skin. Dull tone often has other causes, such as dryness or uneven texture, that call for a different approach.
Sessions, intervals and aftercare
There is no fixed number of sessions. It depends on the type of pigment, its depth, your phototype and how your skin responds. With dermal pigment the pace is slow: in the study of 110 patients, people received between 2 and 9 sessions spaced 3 to 6 months apart, and improvement increased with the number of sessions. In laser toning, by contrast, sessions are closer together and low in energy. The doctor proposes a plan and adjusts it at each review.
During the session your eyes are protected, and the sensation is usually described as small snaps. In the pilot study, the most frequent effects were redness and swelling lasting less than a day. In the dermal pigment study, the aftercare protocol included local cooling and strict sun protection.
For the following days, a simple routine usually helps:
- Gentle cleansing and a soothing moisturiser, without rubbing the area.
- Broad-spectrum sunscreen every morning, reapplied if you spend time outdoors.
- No exfoliants, acids or retinoids until the doctor says so.
- If fine crusts appear, do not pick them.
In Madrid there is usually sun for much of the year, winter included, and indoor heating can dry out the skin. That is why pigment treatments are often planned for autumn and winter, with extra hydration, although the doctor decides on the timing for your case.
Risks: post-inflammatory hyperpigmentation and darker phototypes
The Q-Switched laser acts on pigment, and in skin with more melanin the reaction to inflammation can be more pigment. The Journal of Cutaneous and Aesthetic Surgery letter warns that in skin types IV to VI post-inflammatory hyperpigmentation has to be taken into account, and that Q-Switched lasers can stimulate the surrounding melanin. In the study of 110 patients, 11 people developed post-inflammatory hyperpigmentation, which resolved within 3 to 6 months; the risk was higher with older age, darker skin and darker patches, and in those who also had melasma.
The other risk is light patches. The review on laser toning links mottled hypopigmentation with high accumulated energy, and the review of dermal melanocytosis reports that both hyperpigmentation and hypopigmentation are more frequent at high energies. That is why caution with energy and with the pace of sessions is part of the treatment.
How we work at Santé Madrid
Our clinic is at C. de Amador de los Ríos, 1, Chamberí, 28010 Madrid. This is the usual path when you come in for pigment that will not fade or for a tone that looks dull to you:
- First consultation. You can start with a free aesthetic assessment with a Beauty Coach or with a medical consultation at €50. We go over your history, your medication, your sun exposure and previous treatments.
- Skin assessment. The Santé Madrid medical team examines the type of spot, its colour, your phototype and whether anything needs to be looked into before any laser.
- Plan. The doctor decides whether the Q-Switched head is indicated, with which wavelength and settings, how often, and whether to combine it with home care or other heads.
- Session. Cleansing, eye protection and treatment area by area, adjusting the energy to how your skin responds.
- Follow-up. Before each session we review how your skin has responded and, if any darkening or lightening appears, the plan is adapted or paused.
Treatment is performed by the medical team after the assessment. Results vary from skin to skin, and our aim is a realistic, safe plan for you, not a promise of results.
Frequently asked questions
What is the difference between Q-Switched laser and pulsed light?
Q-Switched is a laser that emits one specific wavelength in nanosecond pulses. Pulsed light emits a broad range of wavelengths that is trimmed with filters. The doctor chooses one or the other depending on the type of spot and your skin.
How do I know whether my pigment is superficial or deep?
Colour gives clues: deep pigment usually looks bluish brown or greyish, and superficial pigment looks brown. But it is the doctor who determines it during the assessment.
How many sessions will I need?
It depends on the type of pigment, its depth and how your skin responds. Dermal pigment usually needs several sessions spaced months apart. The doctor proposes a plan and adjusts it during follow-up.
Does laser toning work for dull tone?
It has been studied mainly in melasma. For dull tone in general there are promising but limited data, such as a small pilot study. The doctor will assess whether it makes sense in your case or whether another approach is better.
Can I be treated if I have dark skin?
The 1064 nm laser is considered relatively safe in darker skin, but the risk of post-inflammatory hyperpigmentation is higher. Treatment is done with more caution and follow-up, and if you are tanned it is best to wait.
What will I notice after the session?
The most common effects are temporary redness or swelling. Protect the area from the sun, do not pick any crusts and message us if something does not progress as we explained.
Is melasma treated the same way as deep pigment?
No. Melasma tends to come back and in some studies it worsened after laser, so it needs a plan of its own with strict sun protection and follow-up.
The Q-Switched laser is a precise tool for pigment, especially when it sits in the dermis, but it requires knowing which spot is present, choosing the energy carefully and respecting the timing. For dull tone, the data are still preliminary. The first step is an assessment with the Santé Madrid medical team.
