Itchy skin and dark patches
As discussed previously, high blood glucose is a cause of dehydration in people with diabetes, and another common sign of diabetic dehydration is itchy and dry skin. The skin usually cracks, and since infections are more common in diabetics, they get infected more frequently.
Another common finding in people with diabetes is dark patches in the skin, which is not associated with dehydration or high blood glucose but insulin resistance instead. This sign is also known as acantosis nigricans, and the characteristic dark patches are usually located in the articulation areas and skin folds. It is a useful sign to detect early diabetes, but it may also be used to recognize patients with metabolic syndrome and pre-diabetic states, especially when they are overweight as well.