Background: A novel day–night facial serum regimen combining antioxidants, hydration-enhancing agents, and bioactive compounds has been developed to address skin aging. Objective: The aim is to explore changes in skin aging parameters and assess the safety and tolerability of a day-and-night facial serum combination. Methods: In this single-arm, non-randomized, prospective, open-label study, 30 participants aged 35–55 years applied a day facial serum (DFS) and a night facial serum (NFS) for 8 weeks. Objective assessments included skin texture and depression (Antera 3D®), elasticity and firmness (Cutometer®), hydration (Corneometer®), TEWL (Tewameter®), melanin index (Mexameter®), and brightness (Colorimeter®). Evaluations were performed at baseline, at 1 month and 2 months after treatment start, and at 1 month post-treatment. Results: Thirty participants (Fitzpatrick III–IV) completed the study. Significant improvements in skin texture (p = 0.002) and reduction in skin depression (−22.7%, p < 0.001) were observed after 2 months. Skin firmness increased significantly at 1 month (p < 0.001) and remained elevated post-treatment (p = 0.008). The melanin index decreased at 1 month (p = 0.048), while hydration declined after discontinuation (p = 0.016). TEWL showed a significant overall time effect; however, no Bonferroni-adjusted pairwise comparison versus baseline was significant. No significant changes were observed in elasticity or brightness. Mild transient burning was the most common adverse event. Other reported adverse events included acne, miliaria rubra, oiliness, and mild itching; all were non-serious and did not result in treatment discontinuation. Conclusions: The combined DFS and NFS regimen was well tolerated and was associated with favorable changes in skin texture and firmness. Transient local reactions, particularly mild burning sensation, were commonly reported but did not result in treatment discontinuation. Further controlled studies are warranted to confirm these observations.
Wanitphakdeedecha et al. (Fri,) studied this question.