Stand-Alone Carboxytherapy Followed by Consolidation with Oral Hydrolyzed Marine Collagen Fragments: A Potential Sequential Bioregenerative Strategy for Hypertrophic Scars: A Case Report

Introduction: Carboxytherapy, via the Bohr effect, a denser dermal environment, and preserved fibroblast function, along with oral administration of bioactive marine collagen fragments that target fibroblasts, are regenerative strategies that could improve scar elasticity, thickness, and hydration. Their sequential combination might be an innovative approach. Methods: In March 2024, a 56-year-old woman began treatment of a large, hypertrophic, partially retracted post-surgical scar in the nasojugal area at the level of the right nasal wing. Ablative techniques were strictly contraindicated; therefore, a regenerative, restructuring approach via carboxytherapy was chosen. A six-session carboxytherapy cycle was performed from October 10, 2024 (T0) to April 3, 2025 (T6). Each session, performed every 15 days, lasted approximately 10 minutes (flow rate: 60 mL/min, 30-G needle, temperature 45°C). Evaluations were conducted after the third (T3) and last (T6) sessions, using the Antera 3D device (quantitative three-dimensional objective analysis of scar depth, texture, erythrosis, and pigmentation) and the POSAS investigator and subject scoring scales. A final injection of persistent hyaluronic acid was performed on April 3, 2025. To support and strengthen the normalization of the scarring process, the first of a twice-yearly oral cycle of hydrolyzed marine collagen fragments began on October 23, 2025. Results: Over the six-month carboxytherapy treatment cycle, the scarred skin area showed significant improvement toward a normal appearance. The vascularity POSAS score (observer component) decreased from 7 at baseline to 3 at T6; the thickness and flexibility scores improved from 5 to 2 and from 7 to 3, respectively. Additionally, the POSAS pain and itching scores (patient component) decreased from 6 to 1. Conclusion: Stand-alone carboxytherapy again appears to be an effective option for hypertrophic, structurally abnormal scars. While further investigations are underway, supplementation with hydrolyzed marine collagen fragments may help maintain the benefits of prior carboxytherapy. Plain Language Summary: Managing postsurgical scars, especially hypertrophic scars, is challenging. Carboxytherapy, the intradermal or subcutaneous administration of carbon dioxide, is well known for reducing the aesthetic and psychological burden of scars. It promotes local vasodilation, improves tissue oxygenation, and induces the production of new, well-organized collagen in the scar area. Emerging research on the skin-restructuring properties of orally absorbed fragments of marine collagen suggests that these bioactive small peptides may also contribute to scar management. These small collagen peptides, produced at the end of the collagen lifecycle when skin collagen breaks down, stimulate skin fibroblasts to produce new collagen. Several marine collagen fragments are identical to the small, bioactive peptides generated by collagen breakdown and likely act similarly. For the first time, the authors tested an innovative regenerative strategy that sequentially combines six sessions of carboxytherapy with long-term supplementation with hydrolyzed marine collagen in a 56-year-old woman. The woman sought treatment for a disfiguring hypertrophic scar on the right nasal wing following surgery for a skin carcinoma. The outcomes of this innovative treatment strategy appear encouraging, though preliminary, as the woman has completed only her first at-home cycle of oral marine collagen supplementation. Progress in the appearance of the disfiguring scar was monitored using a quantitative three-dimensional skin analysis device and the Patient and Observer Scar Assessment Scale (POSAS). Definitive conclusions from any experience with a single patient must await the results of well-designed clinical studies, some of which are already underway.