Background: Esthetically unattractive hyperpigmentation can occur post-inflammatory or as a result of genetic or hormonal influences, UV exposure or medication. Important parameters for the quality of topical treatments are evidence-based in vivo and in vitro efficacy as well as scientifically verified wanted and unwanted effects.
Objectives: This paper will present cosmetic and pharmaceutical topical ingredients against hyperpigmentation that have been proven in scientific studies.
Materials and methods: A search of PubMed database was performed in October 2020 using the various ingredient names, "melasma" and "hyperpigmentation." Two reviewers independently screened titles, leading to the selection of 30 papers.
Results: Hydroquinone, a tyrosinase inhibitor, has been used for over 40 years to treat hyperpigmentation. It is the most commonly studied agent for lightening pigment. Despite the limited evidence-based research on novel treatment approaches, several ingredients did show efficacy as depigmenting agents, including tyrosinase inhibitors, substances that increase cell turnover, and plant derivatives.
Conclusions: Hydroquinone is still the gold standard for the treatment of hyperpigmentation, along with the triple therapy of hydrochinon, tretinoin, and steroids in different modifications. In summary, hyperpigmentation is best treated using a combination therapy of different approaches that includes consequent UV protection.
Keywords: Hydroquinone; Hyperpigmentation; Lentigo; Melanosis; Photoaging.