Phototherapy is a medical treatment that uses light to improve various health conditions. It is commonly used to treat skin disorders like psoriasis and eczema, as well as mood disorders such as seasonal affective disorder (SAD). The therapy involves exposure to specific wavelengths of light, which can help reduce inflammation and promote healing. During phototherapy sessions, patients may sit in front of a special light box or receive treatment with lasers. The duration and frequency of treatment depend on the condition being addressed. Phototherapy is generally considered safe, but it is important for patients to follow their healthcare provider's recommendations.