Why does dry skin itch?

Skin itches as a sign that there’s a threat.¹ In the case of dry skin, the itch is associated with the inflamed, irritated skin barrier. That doesn’t mean all dry skin is itchy, however. Itchiness can be a symptom of other skin conditions too, as Dr. Hope Mitchell points out: “Dermatologists have a saying that we tell our patients: "We don’t know if it’s the rash that itches, or the itch that rashes.” Dry skin as a whole needs a lifestyle treatment plan (gentle products, moisturizing), but the itch itself can be treated with hydrocortisone cream. If the itch is enough to bother you, it’s worth a trip to the dermatologist to check it out.

References:
¹Molecular and Cellular Mechanisms that Initiate Pain and Itch by Jialie Luo, Jing Feng, Shenbin Liu, Edgar T. Walters, and Hongzhen Hu. Cell Mol Life Sci.