the amount of pressure and the duration of the therapy are based merely on empirical observations,11,12 and its efficacy may be limited
by the ability to adequately fit the garment to the wounded area and by reduced compliance due to significant patient discomfort. Silicone-based gels and sheets have been advocated as promising means to reliably improve scar appearance and prevent excessive scar formation. A randomized, double-blind, placebo-controlled study of silicone gel for the prevention of hypertrophic scarring in the medial sternotomy wound showed promising efficacy, with no side effects and satisfactory compliance.13 Although, a recent meta-analysis of 13 trials (including a total of 559 patients) concluded that there was only weak evidence for benefits of this treatment because of the poor study quality and their high susceptibility to bias.14
Thus, robust clinical trials with clear definitions of criteria for scar improvement have largely been lacking, and no treatment or regimen to manage postsurgery scarring has been universally adopted,
although evidence-based medicine in this field is emerging.
The topical scar gel containing extractum cepae, heparin, and allantoin as active constituents has proven its value in both clinical studies and in routine practice for many years.10,15-17 Each constituent has a complementary mechanism of action that may contribute to the therapeutic effect of the medication. By inhibiting excessive fibroblast proliferation and the release of extracellular matrix constituents (eg, proteoglycans) from fibroblasts, extractum cepae counteracts increased scar tissue formation (scar hypertrophy and keloid formation).18-22 Heparin exerts an anti-inflammatory and antiedematous effect, as well as stimulating cell and tissue regeneration in the corium, where it also binds to the surface of scar collagen, inhibiting further collagen polymerization.23,24 Allantoin has a hydrating action, promotes wound healing, and has a soothing effect on irritation.
The aim of the present study was to evaluate the effects of the scar gel containing extractum cepae, heparin, and allantoin on scar maturation after early initiation of treatment in a large, multicenter, observational clinical trial. Physicians from a number of different fields were included in this study to reduce the likelihood of bias, which could arise if the study was limited to physicians from a single
specialty. To the authors’ knowledge, no other studies of scar treatments have included such a large patient population.
The results of this study suggest that early initiation of the scar gel containing extractum cepae, heparin, and allantoin may positively
promote the formation of physiological scars and prevent excessive scarring. At visits 2 and 3, there was a statistically significant
improvement in both scar color and pliability compared with visit 1. At visit 3, which occurred 4 to 5 months after initiating treatment with the scar gel, only about 1% of scars were still rated
as markedly red or markedly hardened compared with 45.7% and 32.2%, respectively, at visit 1. Conversely, 98.9% of scars were rated as normal or slightly hardened, while 99.0% were normal or slightly red. There were also improvements in scar size: mean scar height and mean scar width decreased by 47.8% and 31.5%, respectively. As expected, the treatment had little effect on scar length. Patient-reported assessments of tension, sensitivity to pain, and pruritus showed a statistically significant improvement at both visit 2 and visit 3 compared with visit 1.
Also, in subjective assessments of tolerability, 92% of physicians and patients described the scar gel containing extractum cepae, heparin, and allantoin as either very good or good. However, the specific odor of the scar gel, which is due to the onion extract, has been noted in daily practice in some patients. Nevertheless, the good tolerability and efficacy led to 87% of physicians and 86% of patients concluding that the suitability of the scar gel to early-stage scar treatment was either good or very good.
Many of the beneficial effects of the scar gel containing extractum
cepae, heparin, and allantoin on scar maturation reported here have been already demonstrated in a prospective, randomized,
controlled trial including 65 children who had undergone thoracic surgery. Here, early treatment with the scar gel containing
extractum cepae, heparin, and allantoin starting 2 to 3 weeks after surgery led to a markedly smaller increase in scar size, a