Ichthyosis vulgaris (ik-thee-O-sis vul-GAY-ris) is an inherited skin disorder in which dead skin cells accumulate in thick, dry scales on your skin's surface.
The scales of ichthyosis vulgaris, sometimes called fish scale disease or fish skin disease, can be present at birth, but usually first appear during early childhood. Sometimes, mild cases of ichthyosis vulgaris go undiagnosed because they're mistaken for extremely dry skin.
Most cases of ichthyosis vulgaris are mild, but some are severe. Sometimes other skin diseases, such as the allergic skin condition eczema, are associated with ichthyosis vulgaris. No cure has been found for ichthyosis vulgaris, and treatments focus on controlling the condition.