Desmopressin diabetes insipidus

In central diabetes insipidus a hypophysial malfunction, caused by different diseases as well as head injuries, neurosurgery, or genetic disorders, leads to AVP hyposecretion. This type of diabetes insipidus can successfully be treated by the exogenous administration of AVP or AVP analogues (e.g. desmopressin). 

Desmopressin may be given orally, intranasally, SC, or IV. The oral dose must be determined for each individual patient and adjusted according to the patient s response to therapy. When the drug is administered nasally, a nasal tube is used for administration. The nasal tube delivery system comes with a flexible calibrated plastic tube called a rhinyle. The solution is drawn into the rhinyle. One end is inserted into the nostril and the patient (if condition allows) blows the other end to deposit solution deep into the nasal cavity. A nasal spray pump may also be used. Most adults require 0.2 mL daily in two divided doses to control diabetes insipidus. The drug may also be administered via the SC route or direct IV injection. 

Desmopressin is used for the therapy of diabetes insipidus (ADH deficiency), nocturnal enuresis, thrombasthe-mia (p. 148), and chronic hypotension (p. 314) it is given by injection or via the nasal mucosa (as snuff ). 

Because it is stable, desmopressin is preferred for treatments especially if pressor effects are not desired. The primary indication for therapy is central diabetes insipidus, a disorder that results when ADH secretion is reduced and that is characterized by polydipsia, polyuria, and dehydration. Desmopressin is also used to reduce primary nocturnal enuresis, or bedwetting, in children. It is useful in people with mild hemophilia A or with some types of von Willebrand s disease, in which von Willebrand s factor is present at low levels. In these cases, desmopressin is given when excessive bleeding occurs or before surgery to help reduce bleeding indirectly by increasing the amounts of coagulation factors. 

Central diabetes insipidus Desmopressin is preparation of choice. 

Desmopressin Acetate (DDAVP) Chemically synthesized analogue of arginine vasopressin Treatment of diabetes insipidus... 

Vasopressin and desmopressin are used in the treatment of central diabetes insipidus. They are discussed in Chapter 37. Their renal action appears to be mediated primarily via V2 receptors although Vla receptors may also be involved. 

Vasopressin and desmopressin are treatments of choice for pituitary diabetes insipidus. The dosage of desmopressin is 10-40 meg (0.1-0.4 mL) in two to three divided doses as a nasal spray or, as an oral tablet, 0.1-0.2 mg two to three times daily. The dosage by injection is 1-4 meg (0.25-1 mL) every 12-24 hours as needed for polyuria, polydipsia, or hypernatremia. Bedtime desmopressin therapy, by intranasal or oral administration, ameliorates nocturnal enuresis by decreasing nocturnal urine production. Vasopressin infusion is effective in some cases of esophageal variceal bleeding and colonic diverticular bleeding. 

Desmopressin Activates vasopressin V2 receptors much more than Vi Acts in the kidney to decrease the excretion of water acts on extrarenal V2 receptors Pituitary diabetes insipidus hemophilia A and von Willebrand disease Oral, IV, SC, or intranasal Toxicity Gastrointestinal disturbances, headache, hyponatremia, allergic... 

Desmopressin f/V-deamino-8-D-arginine vasopressin, dDAVP) is a longer acting analogue of vasopressin. It has very little vasoactive effect but is antidiuretic by an action on vasopressin V2 receptors in the renal tubule and is used to treat central diabetes insipidus and nocturnal enuresis. 

Intravenous injection is the most common route although subcutaneous injection may also be used. A concentrated nasal spray formulation has been proved to be efficient for home treatment of patients with bleeding episodes or even minor surgical procedures and has also been used prophylacticly (4). The nasal spray used to treat diabetes insipidus (Desmospray) is too dilute for use in disorders of hemostasis. Similarly, desmopressin in tablet form (Desmotabs) is intended for treatment of nocturnal enuresis in children and is of no use in the treatment of hemostatic disorders. 

There is growing evidence that desmopressin can be used safely in pregnant women and no adverse effects have been reported in either mothers with diabetes insipidus or their babies (71), or in women with clotting factor deficiencies (72). However, the manufacturers advise that it should be used with caution in women with bleeding disorders, who require high doses. 

Carbamazepine increases the release of endogenous antidiuretic hormone and can therefore potentiate the antidiuretic effect of desmopressin. Of 103 children with cranial diabetes insipidus included in a retrospective analysis, 10% became hyponatrcmic (76). The risk of hyponatremia was three-fold higher when desmopressin and carbamazepine were given in combination. 

In 103 children with cranial diabetes insipidus, 3 children who started or had an increase in dose of lamotrigine needed a larger dose of desmopressin, suggesting an effect on the renal tubule or on drug clearance (76). Lamotrigine also increased desmopressin dosage requirements in two other children with cranial diabetes insipidus (78). 

In two children with cranial diabetes insipidus, desmopressin requirements fell while they were taking lamotrigine (590). Lamotrigine may act at voltage-sensitive sodium channels and reduce calcium conductance. Both of these mechanisms of action are shared by carbamaze-pine, which can cause hyponatremia secondary to inappropriate secretion of antidiuretic hormone. 

Two of ten patients taking long-term lithium therapy were thought to have hypothalamic diabetes insipidus, because of a positive response to desmopressin (615). 

Vasopressin and desmopressin are the alternative treatments of choice for pituitary diabetes insipidus. Bedtime desmopressin therapy ameliorates nocturnal enuresis by decreasing nocturnal urine production. Vasopressin infusion is effective in some cases of esophageal variceal bleeding and colonic diverticular bleeding. 

Intranasal Desmopressin is administered intranasally in the treatment of diabetes insipidus salmon calcitonin, a peptide hormone used in the treatment of of osteoporosis, is available as a nasal spray. The abused drug, cocaine, is generally taken by sniffing. 

Because of the pressor properties of vasopressin, this compound has been modified to desmopressin [dez moe PRESS in] (1-desamino-8-D-arginine vasopressin). This analog is now preferred for diabetes insipidus and nocturnal enuresis because it is largely free of pressor effects and is longer-acting than vasopressin. Desmopressin is conveniently administered intranasally. However, local irritation may occur. 

There are two types of disturbances in vasopressin secretion. In central diabetes insipidus, vasopressin secretion is reduced it can be treated by giving vasopressin or desmopressin, which has a longer half-life, by mouth or intranasally. In nephrogenic diabetes insipidus, the plasma vasopressin concentration may be normal but the kidney fails to respond. The latter type of diabetes insipidus does not respond to vasopressin therapy but, paradoxically, can be managed by giving a thiazide diuretic, for example chlortalidone, at a maintenance dose of 50 mg daily. 

For replacement therapy of pituitary diabetes insipidus the longer acting analogue desmopressin is used. 

Desmopressin replacement therapy is the first choice. Thiazide diuretics (and chlortalidone) also have paradoxical antidiuretic effect in diabetes insipidus. That this is not due to sodium depletion is suggested by the fact that the nondiuretic thiazide, diazoxide (see Index), also has this effect. It is probable that changes in the proximal renal tubule result in increased reabsorption and in delivery of less sodium and water to the distal tubule, but the mechanism remains incompletely elucidated. Some cases of the nephrogenic form, which is not helped by antidiuretic hormone, may be benefited by a thiazide. 

Desmopressin Acetate. Desmopressin acetate (DDAVP.Slimale)is.synthetic l-dcsnmino-8-ivargininc va-mpressin. Ils efficacy, ease of administration (intranasal). long duration of action, and lack of side effects make il the dnig of choice for ihe treat meni of central diabetes insipidus. It may al.so be administered intramuscularly or intravenously. Il is preferred lo va.sopressin injection and oral anti-... 

DIABETES INSIPIDUS TREATMENT involves the administration of drugs to counteract the under-production of antidiuretic hormone (ADH vasopressin) by the pituitary gland, which is a characteristic of diabetes insipidus. ADH itself (arginine vasopressin or lysine vasopressin) can be used, as can the analogues desmopressin and terlipressin. These are all (V subtype) VASOPRESSIN RECEPTOR AGONISTS. These agents are discussed... 

Diabetes insipidus is treated by replacing the antidiuretic hormone by administering desmopressin acetate (DDAVP), desmopressin (Stimate), lypressin (Diapid), vasopressin (aqueous Pitressin), and vasopressin tannate/oil (Pitressin Tannate). 

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