Anti-diuretic hormone disorders Flashcards
Examples of ADH disorders?
Diabetes insipidus
Syndrome of inappropriate ADH secretion
What is Diabetes Insipidus
When the body loses too much fluid by over urination.
what are the symptoms of Diabetes Insipidus
polyuria (passing large volumes of urine)
polydipsia (excessive thirst)
What are the two types of DI?
cranial
nephrogenic
what is cranial DI?
The body doesn’t make enough ADH (vasopressin) due to a problem with the hypothalamus or pituitary. (they are unable to regulate the synthesis of ADH)
what is nephrogenic DI?
Kidneys don’t respond to ADH (vaspopressin)
Treatment of cranial DI?
Desmopressin
Treatment of nephrogenic DI?
Thiazide like diuretics
types of thiazide diuretics?
bendroflumethiazide, chlorthalidone, and indapamide
(Thiazide can be used due to their paradoxical side effects of urinary retention)
MoA of desmopressin
- Potent analogue of ADH (vasopressin), will cause the
kidneys to make less/more concentrated urine - Has a longer duration of action than vasopressin
- Does not have vasoconstriction effects like ADH, so will
not increase BP
Use of Desompressin
Diabetes insipidus
Nocturnal enuresis
polyuria/polydipsia after surgery, hypophysectomy
Side effects of desmopressin
Hyponatraemia- can cause too much conservation of water leading to the dilution of sodium (hyponatraemia)
Oedema
Symptoms of hyponatraemia
headaches, N&V
and 3 C’s
coma, confusion and convulsion
Desmopressin- cautions
Hyponatraemia
elderly - increased risk of hyponatraemia and renal impairment
Antiepileptics- most cause Hyponatraemia
oedema- caution with conditions that are worsened with fluid retention
- Heart failure, hypertension and migraines
Desmopressin- contraindication
conditions which require diuretics
history of Hyponatraemia