E Flashcards
Define diabetes insipidus?
Large amounts of dilute urine produced which causes extreme thirst
State the two drugs used to treat pituitary diabetes insipidus?
Vasopressin and desmopressin
Why is desmopressin preferred?
Long acting, more potent and has no vasoconstrictor effect
What drug is used in the differential diagnosis of diabetes insipidus?
Desmopressin (can cause hyponatraemic convulsions)
What drug is used in partial pituitary diabetes insipidus?
Carbamazepine but is unlicensed
Which two drugs treat hyponatraemia?
Demeclocycline and tolvaptan
How does demeclocycline work?
Blocks renal tubular effect of ADH
How does tolvaptan work?
Vasopressin v2-receptor antagonist
State a side effect of tolvaptan?
Rapid correction of hyponatraemia can cause osmotic demyelination
leading to serious neurological events
State a side effect of desmopressin?
Hyponatraemic convulsions
State one interaction with desmopressin?
With TCAS - increases risk of hyponatraemia
State one counselling point with desmopressin?
Stop taking medicine whilst episode of vomiting / diarrhoea
State a MHRA side effect of corticosteroids use?
Central serious chorioretinopathy - retinal disorder
What are the mineralocorticoid side effects?
Potassium and calcium loss (hypokalaemia/hypocalcaemia) - sodium and water retention - hypertension
What are mineral corticosteroids most marked in?
Most marked in fludrocortisone
Significant with hydrocortisone, corticotrophin and tetracosacitide
What are the glucocorticoid side effects?
Diabetes
osteoporosis
muscle wasting
avascular necrosis
peptic ulceration
psychiatric reactions
What are glucocorticoids most marked in?
Betamethasone, dexamethasone and Hydrocortisone
State the conditions a patient can develop after taking prolonged use of corticosteroids?
Increased risk of infections
Increased risk of chicken pox
Increased risk of measles
Increased risk of psychiatric reactions/altered mood/ risk of suicide/depression
REPORT!
Glaucoma, cataracts
Purple stretch marks
Growth restriction in children
Hypertension
Diabetes - can increase blood-glucose concentration levels (polyuria, polydipsia, polyphagia, fatigue, blurred vision)
Osteoporosis
High doses cause Cushing syndrome - moon face, strae, acne
What is Cushing’s syndrome?
Excessive amounts of cortisol in human body
What are symptoms of Cushing’s syndrome?
Increased fat on chest and tummy
Build-up of fat on neck
Red, puffy, rounded moon face,
Purple stretch marks
Low libido
What is the diagnosis test for Cushing’s syndrome:
Overnight suppression dexamethasone test
Low-dose dexamethasone suppression test (LDDST)
Your blood is drawn 6 hours after the last dose. Normally, cortisol levels in the blood drop after taking dexamethasone. Cortisol levels that don’t drop suggest Cushing’s syndrome. In the LDDST test, you will have blood drawn after taking a low dose of dexamethasone.
Dexamethasone is a synthetic glucocorticoid, which is similar to cortisol.
when dexamethasone is present in the body, it mimics the actions of cortisol and suppresses the release of CRH and ACTH. As a result, cortisol production by the adrenal glands decreases (body doesnt think it needs to produce so much cortisol- balance out)
therefore in cushings syndrome As a result, even though dexamethasone is administered, cortisol production remains elevated because the usual regulatory signals to decrease cortisol production are not effectively transmitted.
Which drug is used in management of Cushing’s syndrome?
Metyrapone
Metyrapone acts by blocking the conversion of 11-deoxycortisol to cortisol by P450c11 (11β hydroxylase)
Which drug is used in treatment of endogenous Cushing’s syndrome?
Ketoconazole
State the symptoms of adrenal insufficiency?
Fatigue
anorexia
vomiting
hypotension
hypoglycaemia
hponatraemia
hyperkalaemia