Corticosteroids Flashcards
What are corticosteroids
natural and synthetic substances that mimic the actions of cortisol
what are some physiological effects of corticosteroids
anti-inflammatory
immunosuppressive
metabolic changes (carbohydrate, protein and lipid metabolism)
electrolyte balance and cardiovascular homeostasis.
what are the Lowest doses of corticosteroids used for
treatment of adrenal insufficiency
what are intermediate doses of corticosteroids used for
anti-inflammatory
what are highest doses used for
immunosuppressive
Clinical uses of corticosteroids
Allergies/Anti-inflammatory
Replacement therapy
Immunosuppression
Cancer
What 2 classes of receptors are stimulated by corticosteroid actions
Glucocorticoid
Mineralocorticoid
Glucocorticoid actions
Increased carbohydrate metabolism protein catabolism Fatty acid mobilization Blockade of inflammatory cascade Altered electrolyte and water balance CNS effects
What do adverse effects of glucorticoids correlate with
duration and dose of treatment
Chemistry changes caused by glucocorticoids
↑urine glucose
↑serum cholesterol
↓serum K+
↓measures of thyroid function (TSH, T3, T4) • Suppressed rxn to skin tests
Suppressed test for systemic bacterial infections
Contraindications of glucocorticoids
Untreated pre-existing conditions (bacterial, fungal, viral) High doses in pregnant animals Diabetes Renal disease Heart failure young animals GI ulcers
Group A (short acting glucocorticoids
hydrocortisone, prednisolone, prednisone, methylprednisolone
Group B intermediate acting
triamcinolone
Group C
betamethasone, dexamethasone, dexamethasone sodium phosphate
What are the four chemical classes of glucocorticoids
Group A, B, C, D
What are the classes of glucorticoids based on route
topical agents
inhaled agents
oral agents
systemic agents
T/F All glucocorticoids are synthetic agents
True
Increased GCR and Decreased MCR associated with what
hydroxyl groups on C 21
Is aldosterone a MR or GR
Mineralocorticoid
Pharmocokinetic properties of glucocorticoids
Most elimination by hepatic metabolism
Certain Side chains can delay metabolism and increase duration of action
Most synthetic agents NOT bound to transcortin (which enhances cellular penetration and faster action and doesnt displace endogenous cortisol)
Hydrocortisone
both glucocorticoid and mineralocorticoid actions
given via all routes depending on salt formation
used in large and small animals
Dexamethasone
most widely used across species (widely used in beef and dairy)
long-acting / rapid onset
does not interfere with Addison’s test
routes used for Dex
PO, IM, IV, topical (opthalmic)
Side effects of Dex
colonic perforation and laminitis
