Pharmacology

Question 1

What are the mechanisms of action for enalapril and benazepril? Two answers.

Answer 1

(Inhibition of ACE → prevent vasoconstriction and reduce sodium retention; and balanced vasodilators → reduces preload/afterload, minimizes congestion in tissues and increases tissue perfusion)

Question 2

What is the receptor that telmisartan blocks responsible for?

Answer 2

(AT1 receptor → responsible for vasoconstriction and hypertension)

Question 3

Is the initial bioavailability of telmisartan increased or decreased in fasted cats?

Answer 3

(Increased, doesn’t matter once you reach steady state)

Question 4

How is telmisartan excreted?

Answer 4

(Hepatobiliary)

Question 5

What class of drug is amlodipine?

Answer 5

(Calcium channel blocker)

Question 6

What is the drug of choice for hypertension in cats?

Answer 6

(Amlodipine)

Question 7

What drug is a nonsteroidal estrogen derivative that is used to treat estrogen responsive urinary incontinence in early spay dogs?

Answer 7

(Diethylstilbestrol/DES)

Question 8

Why is the use of diethylstilbestrol/DES strictly prohibited for use in food animals?

Answer 8

(It is potentially carcinogenic in humans)

Question 9

What is the mechanism of action of alpha adrenergic agonists that make them useful in treatment of urinary incontinence?

Answer 9

(They act directly on smooth muscle receptors so they increase urethral tone and maximal urethral closure pressure)

Question 10

What is the FDA approved (in dogs) alpha adrenergic agonist drug?

Answer 10

(Phenylpropanolamine aka proin or proin ER)

Question 11

What class of drugs is used to decrease the tone of the internal urethral sphincter when manual expression or voluntary voiding is nonproductive, reverses alpha effects of nor/epinephrine, and includes the veterinary drug prazosin?

Answer 11

(Alpha adrenergic antagonists)

Question 12

What drug directly stimulates the muscarinic cholinergic receptors on the bladder i.e. stimulates the detrusor muscle to contract and the trigone and sphincter to relax?

Answer 12

(Bethanechol)

Question 13

Severe cholinergic reactions can occur if bethanechol is injected IM or IV, what anticholinergic drug can be administered to reverse those reactions?

Answer 13

(Atropine)

Question 14

Bethanechol can be combined with drugs from the alpha-adrenergic antagonist class, so which drug can it be combined with?

Answer 14

(Prazosin)

Question 15

What class of drug is the preferred pre-anesthetic for blocked animals because they induce muscle relaxation in addition to sedation?

Answer 15

(Benzodiazepines → diazepam and midazolam)

Question 16

In which species does the urinary analgesic phenazopyridine cause methemoglobinemia, hepatotoxicity, and rhabdomyolysis?

Answer 16

(Dogs and cats; it is used in horses and goats after bladder surgery and does not cause the same ADEs in those species)

Question 17

What class of antimicrobials reaches concentrations in urine up to 1000x higher than plasma?

Answer 17

(Beta lactams)