In Nathaniel Hawthorne's 1850 novel The Scarlet Letter, Hester Prynne is sentenced to wear an embroidered scarlet "A" on her chest for the rest of her life — a public, supposedly permanent record of adultery, designed by a Puritan court that wanted the mark to mean something fixed and final. What actually happens to the letter over the seven years the novel covers is stranger than that sentence implies. It does not simply sit there, inert, doing its punitive job. It brightens under certain conditions and seems to fade under others; it resurfaces at moments of stress and exposure in a way that tracks Hester's psychological state more than any court's intention; and by the novel's final chapter, no one — not the magistrates, not Hester herself — is under the illusion that shame or time has scrubbed it away. It has simply become a permanent feature of how she is read.

I open with this because it is close to the best description I know of what patients actually experience with melasma, the most common cause of facial hyperpigmentation I see in clinic. Melasma responds to treatment — often quite well, in the short term. It also, with a frequency that surprises patients far more than it should, comes back. Understanding why has less to do with which cream or laser is used and more to do with where, anatomically, the pigment in melasma actually lives.

Two Layers, and You Can Only Reach One of Them

Melasma is usually described to patients as an epidermal problem — melanocytes in the outermost living layer of skin producing too much pigment, typically triggered by ultraviolet and visible light, hormonal shifts from pregnancy or oral contraceptives, and heat. That description is accurate, but incomplete. Histological work summarized in a 2022 pathogenesis review by Esposito et al. in Dermatology and Therapy documents a consistent dermal component as well: an increased number of dermal melanophages (pigment-laden macrophages sitting below the epidermis), solar elastosis, and an expanded dermal vasculature that appears to actively feed the pigmentary process rather than sit beside it as incidental damage. Most first-line treatments — bleaching creams, chemical peels, most laser settings — are designed to act on the epidermis, because that is the layer within easy reach. The dermal component sits underneath it, largely undisturbed by surface-level treatment, waiting for the same triggers that produced it in the first place to recur. This is the direct biological version of Hawthorne's letter: the visible mark can be scrubbed and lightened, but the deeper condition that keeps producing it was never actually addressed by scrubbing the surface.

The Oral Route: A Real Effect That Doesn't Outlast the Prescription

Oral tranexamic acid has become one of the more evidence-backed systemic options for melasma, and the pivotal data is genuinely encouraging on its own terms. Del Rosario et al. (2018), in a randomized, double-blind, placebo-controlled trial in the Journal of the American Academy of Dermatology (N = 44), gave patients with moderate-to-severe melasma either oral tranexamic acid (250 mg twice daily) or placebo for three months, with both arms also using broad-spectrum sunscreen. The tranexamic acid group showed a significantly greater reduction in MASI (Melasma Area and Severity Index) score than placebo by the three-month mark, with correspondingly higher patient-reported satisfaction. The detail that matters more than the headline result, though, is what the same trial found after treatment stopped: melasma severity in the treated group began trending back upward during the follow-up period once the tranexamic acid was withdrawn. The drug does not appear to reset the underlying condition. It suppresses activity for as long as it is being taken — which is a legitimate and useful clinical tool, but not the same claim as a cure, and it is worth knowing that tranexamic acid's most common side effect in this trial was hypomenorrhea (lighter periods), with the drug generally reserved for patients without a personal or family history of clotting disorders given its antifibrinolytic mechanism.

The Topical Route: Why "Maintenance" Isn't an Upsell

The same pattern shows up with topical treatment. Triple combination cream — fluocinolone acetonide, hydroquinone, and tretinoin, sometimes still called by its original formulation name, Kligman's formula — is one of the most effective topical options available and can clear melasma quite thoroughly over eight to twelve weeks of active use. Arellano et al. (2012), writing in the Journal of the European Academy of Dermatology and Venereology, followed patients who had achieved that initial clearance and compared what happened over the following six months depending on whether they were kept on a structured twice-weekly maintenance schedule or simply stopped treatment altogether. Patients who stopped relapsed markedly more often, and markedly sooner, than those kept on the twice-weekly regimen. Maintenance therapy, in other words, is not a marketing add-on to a melasma treatment plan. It is the part of the plan that determines whether the first part holds.

When Erasing It Harder Makes a Different, Worse Mark

The sharpest version of the Hawthorne parallel shows up with laser toning — low-fluence, low-energy passes of a Q-switched 1064 nm Nd:YAG laser, delivered weekly over a series of sessions, designed to fragment epidermal and superficial dermal melanin gradually rather than in one aggressive pass. It is a genuinely popular option in Asian patients specifically, in part because it avoids the visible crusting and prolonged downtime of more aggressive resurfacing. Choi et al. (2018), studying the modality specifically in Asian patients in the Journal of Cosmetic Dermatology, confirmed real efficacy for pigment reduction — and also underlines the risk that defines this treatment's ceiling: pushed past a certain cumulative dose, across too many sessions at too high a fluence, low-fluence Nd:YAG toning can damage the melanocytes themselves rather than just the pigment they've produced. The resulting complication, well documented across the broader laser-toning literature, is mottled or "salt-and-pepper" hypopigmentation — scattered pale islands where pigment-producing cells have been destroyed, not merely emptied. That complication is typically slower and harder to reverse than the melasma it was meant to treat, because it isn't excess pigment sitting on top of normal skin anymore. It's normal skin that has lost the cells that would have produced pigment at all.

Hawthorne never lets Hester actually remove the letter. What changes by the novel's end isn't the mark; it's the relationship everyone around her has to it, once the town stops expecting the letter to disappear and starts treating its presence as an ordinary, unremarkable fact about her. There's no serious clinical argument for treating melasma with equivalent resignation — the treatments above genuinely work, and are worth using. But there is a very literal version of the same lesson underneath the trial data: melasma is a chronic, relapsing condition, not a stain with a hidden solvent, and the treatments that actually hold up long-term are the ones built around that fact rather than around the promise of a single, final erasure.

References

Arellano, I., Cestari, T., Ocampo-Candiani, J., Azulay-Abulafia, L., Bezerra Trindade Neto, P., Hexsel, D., Machado-Pinto, J., Muñoz, H., Rivitti-Machado, M. C., Sittart, J. A., Trindade de Almeida, A. R., Rego, V., Paliargues, F., & Marques-Hassun, K. (2012). Preventing melasma recurrence: Prescribing a maintenance regimen with an effective triple combination cream based on long-standing clinical severity. Journal of the European Academy of Dermatology and Venereology, 26(5), 611–618. https://doi.org/10.1111/j.1468-3083.2011.04135.x

Choi, J. E., Lee, D. W., Seo, S. H., Ahn, H. H., & Kye, Y. C. (2018). Low-fluence Q-switched Nd:YAG laser for the treatment of melasma in Asian patients. Journal of Cosmetic Dermatology, 17(6), 1053–1058. https://doi.org/10.1111/jocd.12760

Del Rosario, E., Florez-Pollack, S., Zapata, L., Jr., Hernandez, K., Tovar-Garza, A., Rodrigues, M., Hynan, L. S., & Pandya, A. G. (2018). Randomized, placebo-controlled, double-blind study of oral tranexamic acid in the treatment of moderate-to-severe melasma. Journal of the American Academy of Dermatology, 78(2), 363–369. https://doi.org/10.1016/j.jaad.2017.09.053

Esposito, A. C. C., Cassiano, D. P., da Silva, C. N., Lima, P. B., Dias, J. A. F., Hassun, K., Bagatin, E., Miot, L. D. B., & Miot, H. A. (2022). Update on melasma—Part I: Pathogenesis. Dermatology and Therapy, 12(9), 1967–1988. https://doi.org/10.1007/s13555-022-00779-x