The Laser Effect Was Gone by Six Months, and It Landed on the Wrong Side of Zero

Melasma is the pigment condition that breaks people. Not because it is dangerous — it is not — but because it comes back, and it comes back specifically after the thing that was working stops.

So rather than another list of ingredients, this is organized around the two questions that actually decide whether a melasma plan is any good: what shifts it, and what stops it returning.

Who gets it, which is not who you would guess

A database study of 41,283 melasma patients drawn from 108 healthcare organizations found, on race and ethnicity: Asian patients at an odds ratio of 2.0, Hispanic ethnicity at 1.3, and white patients and Black or African American patients both at 0.8.

Both at 0.8. The same figure. Melasma is not a condition of dark skin in a linear way — it clusters in the middle of the range, and the authors read their own data as supporting a preference for melanized phenotypes in Fitzpatrick III to V, less so at the extremes of I, II and VI.

It is 93 percent female. Mean age in that cohort, 48.8. Comorbidity odds ratios worth knowing: rosacea 5.1, atopic dermatitis 3.3, lupus 2.5, hormonal contraception 2.1.

Prevalence overall runs anywhere from 1 to 50 percent depending on which population in which country you measure, which is another way of saying nobody has a global figure. Some 30 to 50 percent of South Americans and Asians can present with it. Among Latino male migrant workers in the US — a population nobody studies — three cohorts came in at 36, 7.4 and 14 percent.

And there is a genetic component that is frequently dismissed. In 686 people across 67 Brazilian families, 38 percent had facial melasma, family history was reported in 40 to 60 percent, and the segregation analysis best fit a dominant pattern interacting with UV and hormonal exposure.

The hormonal triggers, with figures

A prospective Tunisian cohort of 197 women, MASI-scored: pregnancy was an aggravating factor in 51 percent of those who had been pregnant, and oral contraceptive users had roughly eight times the risk of severe melasma. Being under 30, phototype V and major sun exposure each carried about three times the risk.

And a thyroid finding that is forty years old and has not been properly replicated. Lutfi and colleagues, 1985, 84 melasma patients against 24 controls: thyroid disorders in 58.3 percent of melasma patients versus 12.5 percent of controls. Thyroid microsomal autoantibodies in 32.1 percent versus 8.3 percent.

The detail inside it is the useful one. Seventy percent of the women whose melasma began during pregnancy or on the contraceptive pill had thyroid abnormalities, against 39.4 percent of those with idiopathic melasma.

So if it started with a pregnancy or a pill, the thyroid question is worth asking. That is a single 1985 study and the field still leans on it, which I would like to be a less common sentence in this section than it is.

The three topicals with a strong recommendation, and everything else

A 2019 systematic review of 35 randomized trials of topical melasma treatments gave strong clinical recommendations to exactly three things: triple combination therapy, cysteamine, and tranexamic acid. Everything else — niacinamide, kojic acid, arbutin, ascorbic acid — was characterized as low-risk and needing more research, which is a polite way of saying the evidence is not there yet.

Triple combination cream. Kligman’s original 1975 formula was 0.1 percent tretinoin, 5 percent hydroquinone and 0.1 percent dexamethasone, and he found depigmentation was not attainable when any one component was omitted. The modern Cochrane review of 20 trials covering 2,125 people found triple combination beat hydroquinone alone at a risk ratio of 1.58, and beat every dual combination tested. Azelaic acid 20 percent beat hydroquinone 2 percent at 1.25, and did not significantly beat hydroquinone 4 percent. The review’s own verdict on study quality: generally poor.

Tranexamic acid. A meta-analysis of four trials covering 490 patients found oral tranexamic acid added to triple combination cream produced a MASI mean difference of −3.10 against triple cream alone. More importantly: recurrence risk ratio 0.28. That is a roughly 72 percent relative reduction in relapse, which is the number this entire article is organized around. A head-to-head of 50 patients found oral at 250 mg twice daily producing a 58.86 percent MASI reduction over twelve weeks and topical 5 percent producing 50.88 percent, with the difference not statistically significant.

Cysteamine. A meta-analysis of seven randomized trials: 5 percent cysteamine against placebo, standardized mean difference −0.84. Against 4 percent hydroquinone, 0.16 with a p-value of 0.42 — meaning no significant difference. Cysteamine performs about as well as hydroquinone without hydroquinone’s melanocyte toxicity profile, with comparable irritation.

Thiamidol. The largest trial to date, 200 patients: mMASI reduction of 11.8 percent against 5.4 for vehicle at week four, 27.9 against 13.6 at week eight, 36.1 against 16.1 at week twelve. All p<0.001. The study was funded by the patent holder and declares it. And the 24-week study with a regression phase found that at 13 to 20 weeks after stopping, MASI was similar between the active and vehicle groups.

Which is the relapse problem in one sentence, from inside the trial.

And the lasers

This is the finding I would put in front of anyone about to buy a package.

A meta-analysis of 50 studies covering 1,772 patients tracked the effect size of low-fluence Nd:YAG laser toning as monotherapy over time. Under four weeks: −0.51 standard deviations. Four to eight weeks: −0.91. Eight to twelve: −0.97. Twelve to twenty-four: −0.92.

At twenty-four weeks and beyond: +0.01.

Zero. Slightly the wrong side of zero. The effect did not fade, it returned to baseline entirely. Combination therapy did better, holding at −1.45 at twenty-four weeks, and was still declining.

And the complication scales with the treatment: hypopigmentation and leukoderma incidence correlated significantly with the number of laser sessions, p=0.036. So the longer you chase it, the higher the chance of trading a brown patch for a permanent white one.

A network meta-analysis of 39 studies covering 1,394 patients ranked Q-switched Nd:YAG combined with topicals highest at 85.9 percent, ahead of oral tranexamic acid alone at 80.1 percent and microneedling with topicals at 79.7 percent. Note that the top-ranked option is the laser with topicals — never the laser on its own.

The two things that reduce relapse

Adjuvant oral tranexamic acid, at a recurrence risk ratio of 0.28.

And visible-light protection, which has a trial.

Castanedo-Cazares and colleagues randomized 68 patients — 61 completed — all receiving 4 percent hydroquinone, to either a sunscreen protecting against UV and visible light, containing iron oxide, or a UV-only sunscreen at the same SPF 50 or above. Eight weeks. The visible-light group showed 15 percent greater MASI improvement, 28 percent greater colorimetric improvement, and 4 percent greater improvement on histologic melanin assessment.

Same hydroquinone. Same SPF number. The only difference was whether the sunscreen blocked the light past 400 nanometers, and it moved the outcome by a quarter on colorimetry. Why a visible-light sunscreen has to be visible is a physics problem with its own piece.

There is a companion trial, Boukari 2015, on relapse prevention with a visible-light sunscreen, and the relapse percentages usually quoted from it are ones I could not verify against the original — it is a short paywalled research letter and I am not going to print numbers I have only seen second-hand.

Building the plan backwards from the relapse

A tinted sunscreen with iron oxides in it, every day, as the floor — because it is the only intervention with a trial showing it improves the outcome of the treatment you are also doing.

A topical with real evidence: triple combination under supervision for a defined course, or cysteamine, or thiamidol. Not all three. Not stacked with four actives from a routine video.

A conversation with a prescriber about oral tranexamic acid, specifically framed around relapse rather than around clearance, because that is where its best number is.

And a great deal of skepticism about the laser, which produces the fastest visible result of anything on this list, has an effect size of approximately zero at six months, and gets sold in packages of six.

Melasma is a chronic condition. Every treatment in the evidence base performs while you are doing it. Planning for the stopping is the part nobody sells.

This article is educational and is not a substitute for care from someone who can look at your skin. Anything new, changing, painful or spreading should be assessed rather than researched.