Though a healthcare professional usually considers the sensitivity of patients to UV light before creating a phototherapy program and be careful with it, some side effects can still occur. The possible side effects of UVB treatment eczema or psoriasis might include mild sunburn. Sometimes, patients will also experience blisters, itching, stinging sensation, signs of premature skin aging (like loose or leathery skin and dark spots), and cold sores. People who receive this UV light therapy might also experience an increased risk of skin cancer. Considering the side effects you might experience due to the treatment, you are strongly suggested to consult a healthcare professional before applying a UV therapy lamp.