Diabetes%20insipidus Treatment
Principles of Therapy
- Choice of therapy depends on the severity of polyuria
Goals
- Determine and treat the underlying cause
- Adequate hydration and replacement of free water deficit
- Replacement of deficient hormone
Pharmacotherapy
Central DI
Desmopressin
- 1st-line pharmacotherapy agent
- Analogue of naturally occurring vasopressin
- Antidiuretic effect is greater and more prolonged than vasopressin
- Urine volume is decreased and osmolality is increased
- Less vasopressor activity than vasopressin
- Oral, intranasal and parenteral forms are available
Chlorpropamide
- Use is limited to patients who have partial central DI
- Patient still secretes vasopressin but in insufficient quantity
- May work by increasing sensitivity of renal tubules to circulating endogenous vasopressin
- Side effects and limited antidiuretic effect limit their use
Thiazide and Related Diuretics
- Use should be combined with low-osmolar and low-Na diet
- May work by reducing extracellular Na and decreasing glomerular filtration
- Side effects and limited antidiuretic effect limit their use
Carbamazepine
- May enhance the response to ADH
- Can lower urine output by as much as 25-60%
Clofibrate
- Stimulates secretion of AVP
Nephrogenic DI
Desmopressin
- Treatment option for patients with partial nephrogenic DI
Thiazide and Related Diuretics
- Use should be combined with low-osmolar and low-Na diet
- Increase Na loss at the cortical diluting tubule by inhibiting Na reabsorption
- Can reduce urine output by almost 70%
- May combine with potassium (K)-sparing diuretic if hypokalemia occurs
Potassium-Sparing Diuretics
- Eg Amiloride
- Act on the distal renal tubules, cause an increase in the excretion of Na and reduce the secretion of K
- No untoward effects reported when combined with thiazide diuretics to correct hypokalemia
Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)
- Eg Indomethacin, Tolmetin and Ibuprofen
- Prostaglandin synthetase inhibitors which reduce urine flow
- Treatment option for patients not responsive to thiazides and Amiloride
- May have an additive effect with thiazide diuretics in reducing water excretion in some patients
Carbamazepine
- Increase endogenous secretion of AVP
Non-Pharmacological Therapy
Central DI
- Small children with DI may have rapid changes in osmolality
- Family needs to be educated to gauge appropriate fluid intake and urine output
- Daily weight may be used as index of fluid balance
- Regular measurement of electrolytes may be required especially during beginning stages of treatment
- A low-Na and low-protein diet is recommended
- Appetite, linear growth and temperature should be monitored during all clinic visits
Familial
- Genetic counseling and follow-up
Nephrogenic DI
Drug-Induced
- Discontinue offending agent
- May take a few weeks to see improvement
Familial
- Infants: Human milk is preferred because of protein content (6%)
- Decrease Na intake to 0.7 mEq/kg/day
- Children: 8% of total daily calories should be from protein
- Na intake should be <0.7 mEq/kg/day
- Low-Na and low-osmolar diet
- Appetite, linear growth and temperature should be monitored during all clinic visits
- Genetic counseling and follow-up