been identified as “the freckle gene,” and variants in MCR1 are implicated in solar lentigo formation.3
assigned to either the HQ-free four-product kit, which included cleanser, skin brightening complex, sunscreen SPF 30+, and tri-retinol 1.1% products (Facial Cleanser, Lytera Skin Brightening Complex, Daily Physical Defense SPF 30+ Sunscreen, Tri-Retinol Complex ES [SkinMedica]) or the seven-product OMP kit, which included cleanser, toner, HQ 4% (applied twice daily), exfoliant, another HQ 4% (applied once daily), sunscreen SPF 35, and tretinoin 0.025% (Foaming Gel, Toner, Clear Exfoderm, Blender, Healthy Skin Protection SPF 35, Tretinoin Cream [Obagi Medical Products]). The study was conducted over a 12-week period.9 The investigators found equal efficacy among the two commercially available hyperpigmentation kits over the 12-week period.
TABLE 1.1.1 Level and Quality of Evidence for Solar Lentigines Therapies
keratinocytes and the blocking of the conversion of plasminogen to plasmin by TXA has shown to be effective in reducing melanogenesis and UV-induced hyperpigmentation. It has been used to prevent recurrence of solar lentigos treated by lasers and in combination cases of melasma and lentigos. Typical protocols involve nightly topical application from 5 to 18 weeks.10