Effects of Oral Cholecalciferol on Chronic Wound Healing in Patients with Vitamin D Insufficiency or Deficiency

This study found that narrowband UVB light therapy reduced the severity score of atopic dermatitis, a common inflammatory skin disease, by at least 50% for all subjects. The study then looked at the mechanisms of action and found that UVB light therapy suppressed inflammatory Th2 and T22 immune cells and normalized expression of skin barrier proteins to reduce skin thickening due to overactive keratinocytes.

This review provides an summary of the mechanisms thought to be responsible for the therapeutic effects of phototherapy for psoriasis. These mechanisms include through the alteration of the cytokine profile to shift immune response away from inflammatory pathways, through the induction of apoptosis of cells found in psoriasis lesions, and through the promotion of immunosuppression.

This randomized controlled trial compared narrowband UVB light therapy and red light therapy, each used in combination with 2% erythromycin cream, for the treatment of acne. They found that narrowband UVB therapy demonstrated greater efficacy than red light therapy in reducing acne lesion counts and improving overall acne severity.