Hyperpigmentation

Human skin pigmentation and melanin synthesis are incredibly variable, and are impacted by genetics, UV exposure, and some drugs. Patients' physical appearance, psychological health, and social functioning are all impacted by a sizable number of skin conditions that cause pigmentary abnormalities. Hyperpigmentation, where pigment appears to overflow, and hypopigmentation, where pigment is reduced, are the two major classifications of skin pigmentation. Albinism, melasma, vitiligo, Addison's disease, and post-inflammatory hyperpigmentation, which can be brought on by eczema, acne vulgaris, and drug interactions, are the most common skin pigmentation disorders in clinical practice. Anti-inflammatory medications, antioxidants, and medications that inhibit tyrosinase, which prevents the production of melanin, are all possible treatments for pigmentation problems. Skin pigmentation can be treated orally and topically with medications, herbal remedies, and cosmetic products, but a doctor should always be consulted before beginning any new medicine or treatment plan. This review article explores the numerous types of pigmentation problems, their causes, and treatments, as well as the 25 plants, 4 marine species, and 17 topical and oral medications now on the market that have been clinically tested to treat skin diseases.

Post inflammatory hyperpigmentation (PIH) affects all skin types with a heightened predilection for darker skin tones. Its course is chronic once developed and treatment is often difficult. This systematic review aims to summarize the treatment outcomes for PIH with a focus on skin of colour (SOC) individuals. A literature search was conducted using MEDLINE (from 1946), Embase (from 1974), PubMed, and Cochrane in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guideline. Results from 48 studies summarized 1356 SOC individuals. The mean age was 29 years (n = 1036) and 78% were female (n = 786). The ethnic prevalence was 70% Black, 27% Asian, and 3% Latin. Overall, 20% were Fitzpatrick skin type (FST) III, 40% FST IV, 34% FST V, and 6% FST VI. Most cases were precipitated by inflammatory conditions (89%) and localized to the face (83%). The most frequently reported interventions were topical retinoids (22%) and laser therapy (17%). Partial improvement was seen in 85% and 66% of participants, respectively. Laser was the only intervention that offered complete resolution in a subgroup of patients (26%); however, there were reported cases of PIH exacerbation following treatment. Chemical peels (9%) and hydroquinone (7%) were among other treatments with less effective outcomes. PIH and its persistence is a prevalent issue, significantly affecting many affected individuals with darker skin tones. Our results show a lack of robust efficacy across all treatment modalities. There is considerable room for improvement in interventions for at-risk populations.

Melasma is a common pigmentary disorder with a complex pathogenesis, of which the treatment is challenging. Conventional treatment often leads to inconsistent results with unexpected pigmentary side effects and high recurrence rates. Recently, the low-fluence Q-switched Nd:YAG laser (LFQSNY) has been widely used for treating melasma, especially in Asia. We reviewed literatures on the LFQSNY treatment of melasma published between 2009 and May 2022 to evaluate the efficacy and adverse events, including its combination therapy. A systematic PubMed search was conducted and a total of 42 articles were included in this study. It was hard to summarize the heterogenous studies, but LFQSNY appeared to be a generally effective and safe treatment for melasma considering the results of previous conventional therapies. However, mottled hypopigmentation has been occasionally reported to develop and persist as an adverse event of LFQSNY, which may be associated with the high accumulated laser energy. When used aggressively, even LFQSNY can induce hyperpigmentation via unwanted inflammation, especially in darker skin. Although few studies have reported considerable recurrence rates three months after treatment, unfortunately, there is a lack of the long-term follow-up results of LFQSNY in melasma. To enhance the effectiveness and reduce the adverse events, LFQSNY has been used in combination with other treatment modalities in melasma, including topical bleaching agents, oral tranexamic acid, chemical peeling, or diverse energy-based devices, which generally reduced side effects with or without significant superior efficacy compared to LFQSNY alone.

BackgroundMelasma is a chronic, relapsing hyperpigmentation disorder driven by complex interactions among genetic predisposition, hormonal fluctuations, UV exposure, oxidative stress, inflammation, and photoaging. Its psychosocial impact is substantial, especially among women with darker skin types, and treatment remains challenging due to its multifactorial pathogenesis and high recurrence rates.AimsThis review aims to synthesize current knowledge on melasma pathophysiology, highlight recent innovations in topical and procedural therapies, identify limitations of existing treatments, and outline future directions toward personalized and regenerative approaches.Patients/methodsA narrative literature review was performed, summarizing findings from epidemiologic studies, molecular investigations, and clinical trials. Key topics included pigment biology, hormonal and environmental triggers, oxidative stress pathways, emerging depigmenting agents, laser and microneedling technologies, combination therapies, and advances in precision medicine.ResultsMelasma arises from dysregulated melanogenesis involving hyperactive melanocytes, hormonal stimulation, UV-induced oxidative stress, dermal inflammation, fibroblast senescence, and pigmentary incontinence. Innovations include non-hydroquinone brighteners (e.g., thiamidol, melasyl), antioxidants, tranexamic acid, and improved topical delivery systems. Procedural advances-such as low-fluence picosecond lasers, fractional CO2 laser-assisted drug delivery, chemical peel hybrids, and exosome-augmented microneedling-offer enhanced pigment clearance with improved safety profiles. Nevertheless, treatment durability remains limited by relapse, heterogeneous disease subtypes, PIH risk, and inconsistent adherence.ConclusionsMelasma management is evolving toward multi-target, combination-based strategies addressing pigmentation, inflammation, and photoaging simultaneously. Emerging regenerative technologies, biomarker-driven personalization, and AI-assisted assessment hold promise for improving long-term outcomes, though standardized protocols and long-term safety data are still needed.