This study involved developing and evaluating a vitamin D lotion to protect breast cancer patients' skin from radiotherapy-induced dermatitis. This lotion was produced using an emulsion-based system combining vitamin D with excipients for stability and efficacy. Physical and chemical assessments for the lotion in question included pH 5.2, viscosity of 2400 cPs, and spreading pleasingly smoothness. The acceptable range was met; however, sensory testing showed high acceptability scores by patients, as: mean scores were 4.2 for spreadability, 4.4 for absorption, and 4.6 for comfort. Significant reductions in radiation dermatitis severity were established with significant improvement in RTOG/EORTC scores from baseline to week 4: from 3.5 to 1.5, p