Exam 1

Question 1

Inotropic

Answer 1

altering the force of contraction (usually referring to cardiac muscle contraction)

Question 2

Ionotropic

Answer 2

a receptor protein that forms part of a ligand gated ion channel. Receptors attached to an ion channel.

Question 3

What’s the difference between side effects and adverse effects?

Answer 3

Side effects are secondary to the effect intended, while adverse effects are unintended and uninvited (like idiosyncratic reactions).

Question 4

What is the point of a loading dose?

Answer 4

gets plasma to theraputic levels faster

Question 5

T/F: time to achieve steady state is dependent on the dose.

Answer 5

False. It is independent of the dose. Reached after 5 half lives.

Question 6

What is considered a small volume of distribution?

Answer 6

Vd < 1L

Question 7

What does a large Vd (volume of distribution) imply?

Answer 7

drug is preferentially distributed outside of the bloodstream. If it is small, the drug isn’t going to all the tissues of the body.

Question 8

What is the most common type of receptor we are going to see?

Answer 8

Kinase-linked receptors

Question 9

Which receptors are the slowest to produce clinical effects?

Answer 9

Nuclear receptors (intracellular). Found in the cytoplasm.

Question 10

What is receptor down-regulation and what can cause it?

Answer 10

decrease in the # of receptors/effect. Can be caused by chronic exposure to a drug that stimulates the receptor.

Question 11

Which is more common: competitive or non-competitive antagonism? Which is reversible?

Answer 11

Competitive antagonism is both more common and reversible.

Question 12

What is the ceiling effect?

Answer 12

point at which increases in concentration of the drug don’t result in further increase in efficacy.

Question 13

What does a narrow therapeutic index mean?

Answer 13

the dose required to cause death is close to the dose required to have therapeutic effect. This is dangerous.

Question 14

what is mydriasis?

Answer 14

dilation of the pupil

Question 15

What is miosis?

Answer 15

constriction of the pupil.

Question 16

How many drops can the dog/cat eye hold?

Answer 16

one drop.

Question 17

How long should you wait between eye drops?

Answer 17

5 minutes

Question 18

What do we mean when we say a drug is indirect acting?

Answer 18

doesn’t directly interact with the receptor, though it may ultimately result in receptor stimulation.

Question 19

What drugs are miotics and are used for diagnosing parasympathetic lesions?

Answer 19

Pilocarpine

Question 20

Which drug causes cyclopegia?

Answer 20

Atropine. It is an eye analgesic.

Question 21

Which drug is ideal for ophthalmic exams?

Answer 21

Tropicamide.

Question 22

Which drug is most often used to help in diagnosis and localization of Horner’s syndrome?

Answer 22

Phenylephrine

Question 23

What drugs reduce aqueous humor formation/improve aqueous outflow?

Answer 23

Timolol, dorzolamide, latanoprost

Question 24

Dorzolamide is what type of inhibitor?

Answer 24

topical carbonic anhydrase. It reduces aqueous humor production.

Question 25

What does a lacrimogenic do and what is an example of one?

Answer 25

makes eyes produce its own tears again. ex. cyclosporine.

Question 26

What is the main parasympathetic nerve and its main neurotransmitter?

Answer 26

vagus nerve, acetylcholine.

Question 27

What breaks down acetylcholine?

Answer 27

acetylcholinesterases in synapse, pseudocholinesterases in plasma/other tissues.

Question 28

Where is norepi released from?

Answer 28

synaptic nerve endings

Question 29

Where is epi released from?

Answer 29

adrenal glands

Question 30

What receptors does acetylcholine act on?

Answer 30

Nicotinic and muscarinic.

Question 31

Which muscarinic receptors are stimulatory?

Answer 31

M1, M3, and M5

Question 32

What is the most common muscarinic receptor?

Answer 32

M1

Question 33

What are the SEs for agonists of Ach?

Answer 33

SLUDD (salivation, lacrimation, urination, digestion, defecation).

Question 34

T/F: During sympathetic innervation, the iris radial muscle is relaxed.

Answer 34

False. It is contracted.

Question 35

What is the only clinically useful direct acting parasympathomimetic drug? What receptor does it act on?

Answer 35

Bethanechol. Muscarinic receptor agonist.

Question 36

What medication is the reversal agent of choice for reversal of competitive neuromuscular blockers (NMB)? What's its mode of action?

Answer 36

Neostigmine, indirect acting parasympathomimetic.

Question 37

Which drug is the drug of choice for maintenance therapy of myasthenia gravis?

Answer 37

Pyridostigmine.

Question 38

``` Parasympatholytics are generally: A. Muscarinic agonists B. Adrenergic agonists C. Muscarinic antagonists D. Adrenergic antagonists. ```

Answer 38

C. Muscarinic antagonists.

Question 39

What is the most common form of atropine and what is it generally used for?

Answer 39

injectable solution, treatment of bradyarrhythmias/bradycardia.

Question 40

What is commonly seen after IV injection of atropine?

Answer 40

drop in HR, then an increase.

Question 41

Why would you not use atropine in rabbits? What would you use instead?

Answer 41

they have endogenous atropinases which breakdown atropine rapidly. Use glycopyrrolate instead.

Question 42

This direct acting parasympatholytic does not cross the BBB and has a longer duration of action compared to atropine.

Answer 42

Glycopyrrolate

Question 43

These drugs, when used together relax the detrusor muscle, allowing the bladder to fill better. What is their mode of action and which of the 2 can cross the BBB?

Answer 43

oxybutynin and propantheline. Direct acting parasympatholytics. Oxybutin can cross the BBB.

Question 44

T/F: dopamine receptors are adrenergic receptors.

Answer 44

True.

Question 45

What is the rate limiting step/limiting factor when using catecholamines?

Answer 45

tachycardia and tachyarrhythmias.

Question 46

Which drug causes the most renal vasoconstriction?

Answer 46

norepinephrine

Question 47

When is the use of epi indicated? What receptor does it have the most affinity for?

Answer 47

cardiopulmonary arrest/anaphylaxis. Mainly on alpha 1 for vasoconstriction.

Question 48

What are the main clinical effects of norepi?

Answer 48

vasoconstriction (via alpha 1 agonism). One of the most important catecholamine vasopressors. Less of an increase in MvO2 than with epi.

Question 49

What drug causes the strongest vasoconstriction?

Answer 49

Norepinephrine. Stronger vasoconstriction than with similar doses of epi.

Question 50

When norepi is being used, what must always be done?

Answer 50

continuous ECG monitoring.

Question 51

What is the least common catecholamine? Wha receptor does it not act on?

Answer 51

Isoproterenol. No alpha effects.

Question 52

Which drug is the post arrest vasopressor of choice?

Answer 52

Dopamine.

Question 53

When would you use dobutamine?

Answer 53

tx of anesthesia associated hypotension. To maintain cardiac output and tissue/organ perfusion.

Question 54

This drug is a direct-acting alpha 1 selective agonist, non-catecholamine that can be used to stop a nose bleed.

Answer 54

Phenylephrine.

Question 55

These two drugs are non-selective Beta agonists that are used for feed efficiency, weight gain, and carcass leanness.

Answer 55

Ractopamine and zilpaterol.

Question 56

This drug is most commonly used for bronchial asthma. What drug and what is the MOA?

Answer 56

Albuterol, selective beta 2 agonist.

Question 57

What selective beta-2 agonist is contraindicated in food animals? What animal is it used in?

Answer 57

Clenbuterol. Horses as an oral syrup.

Question 58

Terbutaline is available in what forms in animals? What is its MOA?

Answer 58

tablet or injectable. Selective B2 agonist.

Question 59

What mixed sympathomimetic is used to treat urinary incontinence due to urethral sphincter hypotonus/incompetence? It is often used with?

Answer 59

Phenylpropanolamine (PPA, Proin). Estrogens.

Question 60

What is ephedrine used for? How is it administered? What is its MOA?

Answer 60

as a CRI to maintain BP under anesthesia. IV only. Mixed sympathomimetic.

Question 61

What non-specific alpha antagonist is used to treat urinary retention and pheochromocytomas?

Answer 61

Phenoxybenzamine.

Question 62

Is prazosin more or less specific than phenoxybenzamine? When is this drug typically used?

Answer 62

more specific. Used to treat feline lower urinary tract disease and can be adjunctive treatment of CHF, systemic or pulmonary hypertension.

Question 63

This non-specific beta-antagonist readily crosses the BBB and is generally used to treat tachyarrhythmias. It is also used in chocolate toxicity.

Answer 63

Propanolol.

Question 64

What are 2 beta 1 selective antagonists and which lasts the least amount of time?

Answer 64

Atenolol and esmolol. Esmolol is the shortest acting used for supra-ventricular arrhythmias.

Question 65

What drug blocks DOPA decarboxylase in the norepi production pathway?

Answer 65

alpha-methyl dopa.

Question 66

This drug is used to calm equines and blocks NE uptake into the vesicles.

Answer 66

Reserpine

Question 67

How does guanethidine work?

Answer 67

Blocks NE release

Question 68

Which drug is used for the Tensilon test?

Answer 68

Edrophonium