Freckles are benign, pigmented macules commonly seen in people with pale skin and high UV exposure. They result from an excess of melanin, which is produced by both genetic and environmental factors. Key enzymes, including tyrosinase and related proteins, are involved in dysregulated melanogenesis, leading to lesions known as ephelides and solar lentigines. Freckles are an important cosmetic problem, and treatment is sought even when they do not result in any medical issues. Common treatments include topical depigmenting agents such as vitamin C, tretinoin, hydroquinone, and kojic acid, and other physical modalities, which include chemical peels, laser therapy, and cryotherapy. Many successful treatments also have negative side effects including irritation, post-inflammatory hyperpigmentation, increased photosensitivity, and expense. Thus plant-based and herbal alternatives are preferred because of their safety, efficacy and sustainability. Botanicals that show strong anti-melanogenic effects have antioxidant activity, the ability to inhibit tyrosinase, or decreased melanin production by blocking mechanisms related to melanogenic signalling pathways. Examples include Curcuma longa, Carica papaya, Morus alba, Glycyrrhiza glabra, and Camellia sinensis. Preliminary in vitro, and in vivo animal models such as zebrafish and murine studies in the experimental group show depigmenting activity of compounds such as glabridin, curcumin, aloesin, and neocnidilide. Clinical studies proved that herbal therapies can be efficacious in the treatment of hyperpigmentation with minimal side effects. In summary, there is a need for unified evidence of herbal medicines for freckles through clinical trials as well as formulation of better dosage form.
An Open Access, Peer Reviewed Journal in the field of Pharmacognosy
