Glucocorticoids Flashcards
[T/F] In patients with cerebral edema, drugs with high mineralocorticoid activity should be given.
F.
Use corticosteroids with minimal mineralocorticoid activity to reduce water retention.
Most widely used pharmacologic analogue for aldosterone
Fludrocortisone
Why should you follow the circadian rhythm when administering exogenouse cortisol?
Endogenous steroids might not be stimulated –> adrenal insufficiency
What is the permissive effect?
Maintenance of normal BP
In the presence of glucocorticoids, vasoconstriction effects of catecholamines can reverse hypotension
Effect of estrogen on cortisol levels
Increased serum concentration of transcortin –> rise in total amount of cortisol without changing level of free cortisol
Effect of progestogen on cortisol levels
Has high affinity for transcortin, can displace bound cortisol –> increased free cortisol levels
Effect of glucocorticoids in the synthesis of prostaglandins
- Inhibit transcription of gene for cox-2 which is induced in inflammatory cells by inflammatory mediators
- blocks production of arachidonic acid from phospholipids and by phospholipase A2 inhibition
Glucocorticoids: Metabolic Effects
increased protein catabolism, decreased protein synthesis –> muscle atrophy and weakness
Effect of methylation on corticosteroid function
Increased anti-inflammatory activity, improved pulmonary penetration, e.g. methylpredisolone
Effect of fluorination on corticosteroid function
Improved anti-inflammatory effect with pronounced catabolic effect, e.g. dexamethasone
Examples of short-acting glucocorticoids
Hydrocortisone, cortisone
-used during shock because of high mineralocorticoid activity
Examples of intermediate-acting drugs
Methylprednisolone, prednisone, prednisolone, triamcinolone
-only low doses are needed
Example of long-acting drugs
Dexamethasone, betamethasone
-fluorinated
