ENDOCRINE- ANTIDIURETIC HORMONE DISORDERS Flashcards
What is diabetes insipidus?
Different to DM.
Reduced production of ADH means kidney not retaining much water.
Can cause polyuria + polydipsia (thirst)
What is treatment for
CRANIAL diabetes insipidus?
Desmopressin - or drinking more water.
What is treatment of nephrogenic Diabetes insipidus?
Thiazides (paradoxical effect)
What is cause of nephrogenic Diabetes insipidus?
Kidneys do NOT respond to the ADH
What is cause of CRANIAL diabetes insipidus?
Hypothalamus/ pituitary does not make ENOUGH ADH.
What is MOA of desmopressin?
synthetic analogue of vasopressin (ADH)
Causes less urine
What does increase in ADH do to urine output?
Reduced urine output - less water released.
What are 2 advantages of desmopressin?
Longer duration of action
No vasoconstrictor effects
What is use of desmopression?
Diabetes insipidus
Nocturnal enuresis
What are 2 SEs of desmopression?
Hyponatraemia
Oedema
Nausea
What are 3 cautions of using desmopressin (oedema)?
caution in patients who have HTN, HF, Migraine.
What are 3 symptoms of Hyponatraemia?
Headache
N+ V
convulsions
What is a caution of using desmopressin (Hyponatraemia)?
Caution in elderly + epilepsy
What drug increases ADH secretion?
TCA
What 4 drug classes can interact with Desmopressin to cause hypOnatraemia?
TCA, Diuretcs, NSAID, SSRI
What is syndrome of inappropriate antidiuretic hormone secretion (SIADH)?
HypOnatraemia caused by inappropriate ADH secretion = dilute salt in blood as urine not passed out.
What are 2 treatment drugs for SIADH?
1.fluid restriction:
- Demeclocycline
- Tolvaptan
What is Demeclocycline moa?
Blocks renal effect of ADH - causes Diabetes insipidus.
What is tolvaptan class?
V2 receptor antagonist
What is MOA of tolvaptan?
rapid correction
helps increase sodium concentration, reduce urine osmolatiry
Why to avoid rapid correction of hyponatraemia with tolvaptan?
Causes osmotic demyelination
neurological events
What electrolyte to avoid causing with tolvaptan?
avoid hyponatremia.
How is urine concentration in Diabetes insipidus?
More dilute urine
