How does phototherapy work in treating psoriasis?

Eczema and psoriasis share many similarities. They are both chronic skin rashes and present with itchy red rashes. However, have differences in their presentation and have different underlying pathology. Atopic eczema is a form of eczema that often occurs from infancy and childhood. It presents with itchy red rashes that affects mainly the flexural areas, like the elbow and knee bends and neck. In acute eczema, the rash can be weepy and oozy. However, in chronic eczema, the rash is raised and thick and this can resemble psoriasis.

Thanks for the question. If you have a diagnosis of psoriasis, there is a possibility that certain treatments can aggravate it. With psoriasis, damage or injury to the skin can cause psoriasis to develop at the site of the injury. This is know as the Koebner phenomenon. Therefore, you do have to take care that the treatment is gentle and does not cause any trauma or damage to the skin. Likewise, for eczema, the skin is sensitive and more prone to external insults, so you should avoid treatment if the facial skin is still red or irritated as this can be more easily aggravate by treatment.