Lecture 8 2/14/25 Flashcards
What are the characteristics of trilostane/vetoryl?
-used to treat both PDH and ADH
-reversible inhibition
-inhibits glucocorticoid production more than aldosterone and sex hormones
-effective suppression for 8 to 12 hours
-costly in large dogs
Why should trilostane be given with food?
the drug is better absorbed with food, which can lead to better effects of the drug
What are the characteristics of trilostane monitoring?
-want to monitor clinical signs like attitude, appetite, and water intake
-want to titrate dose to effect and change dose as needed
-overtreatment possible; can cause iatrogenic Addison’s
-should do first recheck within 10-14 days of starting medication
What are the monitoring options for trilostane?
-ACTH stim test 4 to 6 hours post pill
-pre-pill and 3 hour post-pill cortisol measurements (better option)
What are the potential side effects of trilostane?
-GI signs/upset
-iatrogenic Addison’s
-worsening of cushing’s signs
What are the characteristics of mitotane?
-used to treat both PDH and ADH
-lowest cost
-dose-dependent destruction of zona fasciculata and zona reticularis (sex hormone production)
-goal is a hypoadrenal state
What are the treatment phases when using mitotane?
-induction/loading
-maintenance
-reinduction
Why might mitotane be chosen over trilostane?
it can provide better control more quickly
What are the characteristics of the mitotane induction period?
-dose is split into twice a day administrations until reduction of clinical signs
-maximum of 7 to 9 day period
-consider restricting food during induction
-monitor appetite and PU/PD
-complete an ACTH stim test at day 7 to 9
What are the characteristics of the mitotane maintenance period?
-induction dose is split into 2 to 3 doses a week
-monitor clinical signs
-provide owner with a rescue prednisone dose for use in the event of Addison’s clinical signs
-monitor ACTH stim +/- electrolytes
What are the potential side effects of mitotane?
-GI signs
-iatrogenic Addison’s
-may be permanent or reversible
What are the characteristics of ketoconazole?
-used to treat PDH and ADH
-inhibits cholesterol entry to adrenal gland
-inhibits cortisol production pathway
-inhibits ACTH release to the pituitary
-similar clinical effects to trilostane
-monitoring as per trilostane
What are the potential side effects of ketoconazole?
-vomiting and anorexia
-idiosyncratic hepatocellular damage that may be permanent
-iatrogenic Addison’s
What are the characteristics of selegiline?
-dopamine agonist
-poor efficacy
-inhibits ACTH release in pars intermedia
-slow onset of action
-may help with cognitive dysfunction
-side effects include GI signs, restlessness, disorientation, hypertension, and drug interactions
-not recommended at UT
What are the characteristics of adrenalectomy?
-surgical treatment for ADH
-curative if surgical resection is successful
-predictors of negative outcome include advanced cushing’s, increased tumor size and invasion, venous thrombosis, and metastatic dz
What are the characteristics of hypophysecectomy?
-potentially curative surgery for PDH in dogs and cats
-increased risk with larger tumors
-must manage patient for polyendocrine disorders following removal, including hypothyroidism, addison’s, and diabetes insipidus
What are the characteristics of radiation therapy?
-can be used for micro- and macroadenomas of the pituitary
-palliative management
-reduces neurologic signs
-reduces medication doses
-improves appetite
-risks include general anesthesia and radiation side effects
How are secondary complications handled?
-treat primary disease
-disease-specific treatment
-monitor closely
What are the treatments for various secondary complications to cushing’s?
-hypercoagulability: anticoagulants
-systemic hypertension: ACE inhibitors or ARBs
-proteinuria: ACE inhibitors or ARBs; lower protein diet
-urinary tract stones: diet changes +/- urolith removal
What are the characteristics of cushing’s prognosis?
-variable
-overall mean survival around two years
-can have survival greater than four years in animals with good response to treatment
