Efficacy and Safety of Long-Pulsed 755-nm Alexandrite Laser for Keratosis Pilaris: A Split-Body Randomized Clinical Trial

This study evaluated the efficacy and safety of long-pulsed 755-nm alexandrite laser treatment for keratosis pilaris (KP) in a split-body randomized clinical trial involving 22 patients. After four treatment sessions, the laser-treated side showed significant improvements in total, roughness, and redness scores according to both physicians' and patients' assessments. Dermoscopic and ultrasonographic evaluations revealed excellent improvements in follicular plugs, perifollicular erythema, perifollicular hyperpigmentation, and epidermal bulges on the laser-treated side compared to the control. Histopathology confirmed improvements in follicular plugs and inflammatory cell infiltration. The treatment was deemed effective and safe, with only three patients experiencing reversible postinflammatory hyperpigmentation.