Published 2 June 2026 · Updated 9 September 2026
Picosecond lasers arrived with a straightforward pitch: shorter pulses than the nanosecond Q-switched machines they sit alongside, so pigment is disrupted mechanically rather than mainly by heat. The physics is real. Whether it produces a better outcome depends on what you are treating — and for one common condition the published evidence points away from picosecond technology rather than towards it.
This page compares the two by indication rather than by specification sheet.
The actual difference between them
Q-switched lasers deliver energy in nanoseconds and work mainly through a photothermal effect: pigment absorbs light, heats rapidly and fragments. Picosecond lasers compress the same energy into a shorter pulse, which shifts the mechanism towards photomechanical disruption, with less heat spreading into surrounding tissue.
The size of that gap is worth stating plainly, because it is routinely overstated. A picosecond alexandrite laser of the type used at MED YU MED runs at 750 picoseconds. A Q-switched Nd:YAG typically runs at 5 to 20 nanoseconds. That is roughly seven to twenty-five times shorter — not the thousandfold difference the unit names suggest, since a nanosecond contains a thousand picoseconds but the machines do not sit at the extremes of their ranges.
Less heat is the clinically interesting part, because heat drives post-inflammatory hyperpigmentation — the complication that matters most on the skin types common in the Gulf.
Tattoo removal: a real but narrower advantage
A 2012 prospective trial in Archives of Dermatology enrolled 15 patients with dark-pigmented tattoos, of whom 12 completed the study, and concluded that the picosecond 755-nm alexandrite laser is a safe and very effective procedure for removing tattoo pigment. That is a small trial on one category of ink, and the caveat below applies to it as much as to any other study here.
Where the advantage narrows sharply is the comparison nobody advertises. A 2018 retrospective study in the Journal of Cosmetic and Laser Therapy compared an alexandrite picosecond laser at 750 picoseconds in 40 patients against a Nd:YAG nanosecond laser at 5 to 20 nanoseconds in 32 patients, all removing blue-black eyeliner tattoos more than ten years old. The median number of treatments was one. After a single session there was no difference between the two lasers, and no difference in the proportion achieving excellent clearance. The authors concluded that for this indication the picosecond laser does not provide better clearance than the nanosecond device.
So the honest summary for tattoos is: picosecond technology generally reaches comparable clearance in fewer sessions, and on some inks it is clearly better — but not on every ink, and not in every study. As a 2020 retrospective cohort of 214 patients in the same journal noted, the studies suggesting picosecond lasers achieve identical or better results in fewer sessions are limited by very small sample sizes and short follow-up.
Tattoo and permanent makeup sessions carry their own risk profile — blistering, crusting, temporary or lasting pigment change and, near the eye, ocular injury. Read the risk section below before booking.
Cosmetic tattoos and paradoxical darkening
Permanent makeup is a separate problem from body ink. A 2022 study in Lasers in Medical Science compared picosecond against Q-switched Nd:YAG on white, flesh-coloured and brown inks, in the laboratory and in an animal model across four monthly sessions. The picosecond laser outperformed Q-switched on flesh-coloured inks, while white and brown responded similarly to both, and paradoxical darkening of white and flesh-coloured inks was significantly lower with the picosecond laser.
One limit matters when reading this. The animal comparison was run at 1064 nm, and the authors framed their conclusion around the 1064 nm picosecond Nd:YAG. MED YU MED runs a 755 nm picosecond alexandrite. The general principle — shorter pulses produce less paradoxical darkening than nanosecond pulses — carries across, but the specific comparison was not made at our wavelength, and we are not claiming that it was.
Paradoxical darkening is the risk specific to cosmetic tattoos. Inks containing iron oxide or titanium dioxide, common in brow, lip and light-toned work, are the recognised culprits: laser light reduces them to darker compounds, and the colour change happens immediately rather than as part of healing. Picosecond technology reduces that risk without eliminating it, which is why the pigment and its response should be assessed on a small area before anyone treats a whole brow.
Melasma: where the evidence favours the older technology
This is where marketing and data part company.
A network meta-analysis published in the Journal of Cosmetic Dermatology in 2023 pooled 39 clinical studies covering 1,394 participants and ranked laser-related therapies for melasma by their effect on the Melasma Area and Severity Index. Q-switched Nd:YAG combined with topical medication came out ahead of Q-switched alone (mean difference −4.21, 95% CI −6.80 to −1.63), ahead of Er:YAG with topicals, and ahead of picosecond laser with topicals (mean difference −4.80, 95% CI −9.33 to −0.27). Microneedling with topical medication outperformed picosecond laser used alone. Ranked by cumulative probability, the top five were Q-switched Nd:YAG with topicals (85.9%), oral tranexamic acid (80.1%), microneedling with topicals (79.7%), Q-switched Nd:YAG with intense pulsed light (78.9%) and fractional CO2 with topicals (70.5%).
Read that ranking with its limits attached. Much of the picosecond-versus-Q-switched comparison in a network meta-analysis is indirect rather than head-to-head, the confidence interval for that comparison runs from −9.33 to −0.27 and so nearly touches zero, and cumulative-probability percentages are a ranking device rather than a verdict. The authors themselves note that the choice should also weigh adverse effects, skin type and how long the melasma has been present.
Two things still follow. No laser is a standalone answer for melasma — every top-ranked option pairs a device with topical treatment or uses medication alone. And on this ranking, presenting any single device as the definitive melasma solution runs ahead of the published evidence.
Where picosecond technology holds up
Dermal pigment is the clearer case. A study in Lasers in Surgery and Medicine treated 13 patients of Chinese skin type with a picosecond 755-nm alexandrite for benign pigmentary lesions including nevus of Ota, café-au-lait patches, lentigines and Hori’s macules. One patient with nevus of Ota cleared completely after four treatments and two others reached excellent clearance after three and four. Two patients (4.8%) developed transient hypopigmentation that improved at follow-up, and none developed post-inflammatory hyperpigmentation. The authors concluded that picosecond lasers appear to carry a much lower risk of post-inflammatory hyperpigmentation for pigmentary lesions in Asian skin.
Skin type changes the calculation
Dubai’s population skews towards Fitzpatrick types III to V, and darker skin carries a higher risk of post-inflammatory hyperpigmentation after any pigment-directed laser. Here the numbers favour the newer technology: Q-switched lasers carry a reported risk of up to 25% in patients with skin of colour, while a 2019 study of a dual-wavelength picosecond laser reported 4.8%, with blistering in 6.5%.
That is a real advantage, not a guarantee. Picosecond lasers still cause pigment changes. The same 2019 study is a useful reality check on session counts: reaching at least 50% clearance took an average of one session for freckles and café-au-lait macules, 1.5 for lentigines — and 4.5 for melasma. In that series 63% of patients reported satisfaction, 27% were neutral and 9% were very dissatisfied.
What to ask before booking
Useful questions: which wavelength is being used and why; whether a test spot comes before treating a whole area; whether the plan includes topical treatment and photoprotection or only device sessions; how many sessions are estimated and on what basis; what eye protection is used if the treatment area is near the eye; and what happens if the pigment darkens rather than clears. A treatment plan for melasma that consists only of laser sessions is missing the component that carries most of the evidence.
Risks and who should postpone
Both laser types can cause redness, swelling, pinpoint crusting and temporary darkening of treated pigment. Burns sit at the severe end: an area that turns white, grey or leathery, or a blister larger than the treated spot, is a burn and needs same-day assessment rather than aftercare cream. Scarring is uncommon but possible, more so after tattoo work, if crusts are picked, or if a treated area becomes infected; textural change and persistent redness can last months. Post-inflammatory hyperpigmentation is the common complication on darker skin, and patchy loss of pigment is less common but may be long-lasting.
Treated pigment often darkens before it clears, which is expected on sun spots. On permanent makeup a colour change may be the complication itself rather than a stage of healing.
Treatment near the eye carries a specific and serious risk. Brow, lash line and eyelid pigment sit millimetres from the eye, and laser energy in this area has caused iritis, anterior uveitis, iris atrophy and lasting pupil distortion. External goggles are not sufficient for eyelid or lash line work — that requires intraocular metal eye shields fitted under topical anaesthetic. Ask any clinic, including this one, what eye protection it uses before agreeing to periorbital pigment work, and do not proceed without a clear answer.
MED YU MED does not perform laser pigment treatment during pregnancy and breastfeeding; with active infection, inflammation, open wounds or herpes in the treatment area; on a fresh tan, recent intensive sun exposure or sunburn; with active cancer or ongoing cancer treatment; with uncontrolled chronic, endocrine or autoimmune conditions; with photosensitivity or use of photosensitising medication; after recent isotretinoin; after recent use of retinoids, acids or aggressive peeling; with uncontrolled diabetes or impaired wound healing; with a keloid tendency or abnormal scarring risk; where suspicious pigmented lesions require dermatologist assessment first; or under 18. Two additions worth raising at consultation: current or previous treatment with gold salts, which carries a risk of permanent blue-grey discolouration after laser, and self-tanning products used recently on the treatment area, which need at least two weeks and full exfoliation first. A history of cold sores does not necessarily rule out lip or perioral work, but it needs to be declared so the doctor can decide on antiviral prophylaxis; active herpes postpones treatment. Final suitability is determined by a specialist at an in-person appointment.
What MED YU MED performs, and what it does not
The clinic runs the PicoSure Pro, a 755-nm picosecond alexandrite laser, for pigmentation, sun spots, melasma, tattoo and permanent makeup removal. Pricing depends on the zone: general pigmentation from 1000 AED, melasma from 1500 AED, a single upper or lower eyelid from 700 AED, tattoo removal from 300 AED for the smallest size, permanent makeup from 600 AED for a brow tip. The final cost depends on the area, the pigment and the number of sessions.
What this means for melasma specifically. MED YU MED does not operate a Q-switched Nd:YAG — the device that the 2023 network meta-analysis ranked first for melasma when combined with topical medication. We state this on a page that sells picosecond treatment because you should know it before booking rather than after. Melasma is managed rather than cured, no device works as a standalone answer for it, and the doctor will set out the realistic options at assessment, including approaches this clinic does not perform.
Laser pigment treatment is a medical procedure with contraindications and possible side effects, listed above. A quoted price is not an indication that the treatment is appropriate for you. Details and the current price list sit on the PicoSure Pro page.
When to seek help
Call 998 (Dubai Ambulance, free and available 24 hours) or go to the nearest emergency department immediately if you develop difficulty breathing, swelling of the face, lips or tongue, a spreading rash, fainting, a fever above 38.5 °C, or spreading redness with severe pain in the treated area. Do not wait for the clinic to open.
After any treatment near the eye — brow, lash line or eyelid — go to an emergency department or an ophthalmologist the same day if you develop eye pain, light sensitivity, blurred or reduced vision, a pupil that has changed shape, or persistent watering. Do not wait for these to settle overnight. Tell the treating team that you have had laser treatment near the eye, and when.
Contact the clinic during opening hours (10:00–22:00, +971 52 184 5011) if you develop increasing pain, spreading redness, pus, or blistering you were not warned about. If the treated area turns white, grey or leathery, or a blister forms larger than the treated spot, seek assessment the same day — at a DHA-licensed urgent care if the clinic is closed. An unexpected colour change in treated permanent makeup is not an emergency and does not need an emergency department, but contact the clinic and do not book further sessions anywhere until the area has been reassessed. Outside opening hours, contact any DHA-licensed urgent care or emergency department. The clinic is not a 24-hour service. If you have already left the UAE, attend local urgent care and tell them the wavelength, the date and the area treated.
Related reading
For the device specification, see the PicoSure Pro treatment page. For laser resurfacing aimed at texture rather than colour, see MOXI laser therapy, and for colour problems treated with broadband light, see BBL phototherapy.
Frequently Asked Questions
Is a picosecond laser always better than Q-switched?
No. For most tattoos picosecond lasers reach comparable clearance in fewer sessions and cause less paradoxical darkening of cosmetic inks, but a direct comparison on long-standing blue-black eyeliner tattoos found no difference between the two. For melasma, a network meta-analysis of 39 studies ranked Q-switched Nd:YAG combined with topical medication first, ahead of picosecond laser with topicals. The right answer depends on what is being treated, not on which machine is newer.
How much shorter is a picosecond pulse, really?
A picosecond alexandrite laser runs at about 750 picoseconds; a Q-switched Nd:YAG typically runs at 5 to 20 nanoseconds. That is roughly seven to twenty-five times shorter. The thousandfold figure often quoted comes from the units — a nanosecond contains a thousand picoseconds — not from the machines themselves.
Which is safer for darker skin?
The reported numbers favour picosecond lasers. Q-switched systems carry a risk of post-inflammatory hyperpigmentation of up to 25% in patients with skin of colour, while a 2019 study of a dual-wavelength picosecond laser reported 4.8%, with blistering in 6.5%. That is a real advantage on Fitzpatrick types III to V, not a guarantee. Conservative settings, correct wavelength, a test spot and strict sun protection matter more than pulse duration alone.
Can either laser cure melasma?
Neither cures it. Melasma is managed rather than cured — it responds to treatment and returns with sun and hormonal triggers. Every top-ranked option in the pooled analysis pairs a device with topical treatment or uses medication alone, so a plan built on laser sessions without topical treatment and photoprotection is missing the part that carries the evidence. MED YU MED does not operate a Q-switched Nd:YAG, the device ranked first in that analysis, and says so before you book.
Why did my permanent makeup turn dark after laser?
Inks containing iron oxide or titanium dioxide, common in brow, lip and light-toned work, reduce to darker compounds when hit by laser light. This is paradoxical darkening, and it happens immediately rather than as part of healing. Comparative work found it significantly less frequent with picosecond than with Q-switched lasers, but it is not eliminated. It is not an emergency — contact the clinic, and do not book further sessions anywhere until the area has been reassessed.
What about treatment near the eye?
Brow, lash line and eyelid pigment sit millimetres from the eye, and laser energy there has caused iritis, anterior uveitis, iris atrophy and lasting pupil distortion. External goggles are not sufficient for this area — intraocular metal eye shields are the standard. Ask any clinic what eye protection it uses before agreeing to periorbital work. If you develop eye pain, light sensitivity, blurred vision or a change in pupil shape after treatment, seek ophthalmology assessment the same day.
Commercial interest disclosure: MED YU MED provides picosecond laser treatment as a paid service. This page discusses a technology the clinic sells, and states where the published evidence favours a device the clinic does not operate.
Medical disclaimer: This page is for informational purposes only and does not replace a medical consultation.
License statement: MED YU MED operates under DHA License 6589480.
Individual results caveat: Results vary by diagnosis, skin type, and individual response.
References
- Saedi N et al. Treatment of tattoos with a picosecond alexandrite laser. Arch Dermatol. 2012. doi:10.1001/archdermatol.2012.2894
- Zhang M et al. Comparison of treatment with an Alexandrite picosecond laser and Nd:YAG nanosecond laser for removing blue-black Chinese eyeliner tattoos. J Cosmet Laser Ther. 2018. doi:10.1080/14764172.2018.1444773
- Pedrelli V et al. Picosecond laser versus historical responses to Q-switched lasers for tattoo treatment. J Cosmet Laser Ther. 2020. doi:10.1080/14764172.2021.1886307
- Ma J et al. Comparison of laser-related therapies for melasma: a network meta-analysis. J Cosmet Dermatol. 2023. doi:10.1111/jocd.16006
- Chan JC et al. The use of a novel picosecond alexandrite laser for benign pigmented lesions in Chinese skin. Lasers Surg Med. 2016. doi:10.1002/lsm.22443
- Picosecond versus nanosecond Nd:YAG lasers for the removal of cosmetic tattoos. Lasers Med Sci. 2022. doi:10.1007/s10103-021-03400-3
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