This, however, is not a diagnostic finding, as it depends on patient hydration.Desmopressin can also be used; if the patient is able to concentrate urine following administration of desmopressin, then the cause of the diabetes insipidus is neurogenic diabetes insipidus; if no response occurs to desmopressin, then the cause is likely to be nephrogenic. Treatment
Persons with nephrogenic diabetes insipidus will need to consume enough fluids to equal the amount of urine produced. Any underlying cause such as high blood calcium must be corrected to treat nephrogenic diabetes insipidus. The first line of treatment is hydrochlorothiazide and amiloride. Patients may also consider a low-salt and low-protein diet.Thiazide diuretics are used in treatment because diabetes insipidus causes the excretion of more sodium than water, while maintaining the corticomedullary gradient (not maintained when using loop diuretics). The maintained corticomedullary gradient allows more absorption of water in the collecting duct. This improves the blood osmolarity and prevents hypernatremia.High serum osmolarity stimulates polydipsia in an attempt to dilute the serum back to normal and provide free water for excreting the excess serum solutes. However, since the patient is unable to concentrate urine to excrete the excess solutes, the resulting urine fails to decrease serum osmolarity and the cycle repeats itself, hence polyuria. Etymology
The name of the disease comes from:

diabetes: from Latin: diabetes, from Ancient Greek: διαβήτης diabḗtēs "a passer-through; siphon", from Greek διαβαίνειν diabaínein "to pass through", from δια- dia- "through" + βαίνειν baínein "to go".
Erythema multiforme (EM) is a skin condition that appears with red patches evolving into target lesions, typically on both hands.It is a type of erythema possibly mediated by deposition of immune complexes (mostly IgM-bound complexes) in the superficial microvasculature of the skin and oral mucous membrane that usually follows an infection or drug exposure. It is an uncommon disorder, with peak incidence in the second and third decades of life. The disorder has various forms or presentations, which its name reflects (multiforme, "multiform", from multi- + formis). Target lesions are a typical manifestation. Two types, one mild to moderate and one severe, are recognized (erythema multiforme minor and erythema multiforme major). Erythema multiforme was first described by von Hebra in 1860. Signs and symptoms
The condition varies from a mild, self-limited rash (E. multiforme minor) to a severe, life-threatening form known as erythema multiforme major (or erythema multiforme majus) that also involves mucous membranes. Consensus classification:
Erythema multiforme minor—typical targets or raised, edematous papules distributed acrally
Erythema multiforme major—typical targets or raised, edematous papules distributed acrally with involvement of one or more mucous membranes; epidermal detachment involves less than 10% of total body surface areaStevens–Johnson syndrome and toxic epidermal necrolysis used to be considered part of the erythema multiforme spectrum, but that is no longer the case.The mild form usually presents with mildly itchy (but itching can be very severe), pink-red blotches, symmetrically arranged and starting on the extremities. It often takes on the classical "target lesion" appearance, with a pink-red ring around a pale center.