Verapamil‐containing silicone gel reduces scar hypertrophy

A hypertrophic scar is a common dermal fibroproliferative lesion usually treated with topical silicone. Verapamil, a type of calcium channel blocker, is considered a candidate drug for the treatment of hypertrophic scars. Here, we report that the addition of verapamil to topical silicone gel enhances treatment outcomes of hypertrophic scars. Upon creation of hypertrophic scars with the rabbit ear model, varying concentrations of verapamil‐added silicone gel (0.1, 1, and 10 mg/g) were applied daily for 28 days. After the animals were euthanised, microscopic measurement was performed for (a) scar elevation index (SEI), (b) fibroblast count, and (c) capillary count. On gross analysis, features of hypertrophic scars were significantly alleviated in the verapamil‐added groups. On histologic examination, verapamil‐added groups showed (a) reduced SEI (1.93 (1.79‐2.67) for control vs 1.34 (1.21‐1.51) for silicone only and 1.13 (1.01‐1.65) for verapamil‐added silicone), (b) fibroblast count 700.5 (599.5‐838.5) for control, 613.25 (461‐762.5) for silicone only, and 347.33 (182.5‐527) for verapamil‐added silicone), and (c) capillary formation (52 (35.5‐96.5) for control, 46 (28‐64.5) for silicone only, and 39.83(24‐70) for verapamil‐added silicone) (Kruskal‐Wallis test, P