Glucocorticoids Flashcards
Mechanism of GC action (2)
- turns off COX2 synthesis
2. turns on synthesis of product that inhibits PLA2
The long term administration of large doses of prednisone will cause the least reduction in the synthesis of….
a. cortisol
b. ACTH
c. CRF
d. Aldosterone
e. GH
D. aldosterone
GCs effects of vascular events?
reduced vasodilation
decreased fluid exudation
GCs effects on cellular events?
decrease in accumulation / activation of inflammatory immune cells
GCs effects on inflmmatory immune mediators
decrease
GC block (immune elements?
T cell activation
Cytokine production
eosinophil mediator release
mast cell mediator release
GC and 11 keto vs 11 hydroxyl?
11 keto can’t be topical because must be activate in liver to 11 hydroxyl
which two glucocorticoids are 11keto
prednisone
cortisone
A patient with dehydration and hyponatremia would most benefit from?
a. dexamethasone
b. prednisone
c. prenisolone
d. fludrocortisone
e. triamcinolone
fludrocortisone because increases MC activity
liver GC metabolism?
activating converts cortisone to cortisol 11b-hsd1
kidney GC metabolism
inactivating converts cortisol to cortisone 11b-hsd2
fetus GC metabolism
only has 11B-HSD2 (inactivator)
adverse effects of pharmacologic doses unlikely to be seen with dexamethasone but possible with prednisone are? (2)
fluid retention and
hypokalemia
because prednisone has some MC activity whereas dexamethasone has none
hydrocortisone
GC effect? IS effect? Topical? MC? Potency? Forms?
hydrocortisone is basically cortisol
it’s anti-inflammatory effect is the reference - 1 GC/IS; it’s topical activity is 1; its salt retaining activity is 1; and its potency is 20;
comes in oral, injectable, and topical forms
thus must be 11ox
cortisone relative to hydrocortisione?
slightly less AI (GC/IS) activity 0.8; no topical activity (11=o); slightly less MC 0.8; Potency 25eod; only oral
prednisone relative to hydrocortisone?
4x AI (GC/IS)
No topical (11=O)
0.3 MC
Potency 5 eod (relative to 20)