Dry skin patches usually develop when the skin loses moisture because of cold weather, low humidity, hot water, harsh soaps, or irritating products. They may also result from eczema, psoriasis, contact dermatitis, or a fungal infection, especially when the area is itchy, inflamed, scaly, spreading, or slow to heal.
Mild cases often improve with a gentle cleanser, a regular moisturizer, and reduced exposure to known irritants, while persistent, painful, bleeding, or changing patches may require medical evaluation.