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
Triamclinone
Poorly soluble ester / long acting
lasts for weeks to months
Probably only use to treat a cat that is hard to medicate
little to no mineralcorticoid activity
How is triamclinone administered
Orally, inhaled, topical, or parenteral
Prednisone/ Prednisolone
More mineralocorticoid activity than other drugs
Prednisone:
Not well absorbed in horses or cats
Not well metabolized by cats
Use prednisolone for cats and horses
Prednisone metabolized to prednisolone in the liver
methyl-prednisolone
similar to pred but devoid of mineralocorticoid action
what are the 2 types of methyl-pred
Sodium Succinate (water soluble / fast acting Acetate (long acting / insoluble suspension)
Short acting steroid t1/2 < 12 hrs
hydrocortisone
Intermediate acting steroid t1/2 12-36 hrs
triamclinone, prednisone, methyl-pred
long acting steroid t1/2 >48hrs
Dexamethasone
Dexamethasone side effects
GI bleeding/ colonic perforation
laminitis in horses
Hydrocortisone warnings
wear gloves and wash hands after applying to animal
Triamclinone side effect
laminitis in horses
Prednisone contraindication
Don’t use in animal with severe bacterial or fungal infections
Prednisolone contraindication
dont use in animals with corneal ulceration
Methyl-pred warning
Shake before use
What is the only corticosteroid to potentially improve outcome in acute spinal cord injury
Methyl-prednisone sodium succinate
