Veterinary Pharma - General Pharmacology B

Question 1

Which of the following is the main neurotransmitter for the presynaptic nerve terminal of the parasympathetic nervous system?
a.GABA
b.Norepinephrine
c.Epinephrine
d.Acetylcholine

Answer 1

Acetylcholine

The main presynaptic and postsynaptic neurotransmitter for PNS is AcH. Acetylcholine also serves as the main neurotransmitter for the postsynaptic nerve terminals of the SNS

Question 2

Which of the following processes is not a part of the Phase 1 of biotransformation?
a.Oxidation
b.Acetylation
c. Hydrolysis
d.Reduction

Answer 2

Acetylation

Phase I metabolism includes four major pathways: oxidation, reduction, hydrolysis, and hydration, among which oxidation is the most important. Phase I products act as substrates for Phase II processes, resulting in conjugation with endogenous compounds

Question 3

Which of the following statements about drug absorption is true?
a. Drugs undergoing first pass metabolism will have increased concentration in the blood
b.Ionized drugs are absorbed much more readily than unionized drugs
c.Basic drugs are absorbed readily in acidic parts of the GI tract
d.Drugs that are highly hydrophilic are poorly absorbed

Answer 3

Drugs that are highly hydrophilic are poorly absorbed

Majority of barriers between body compartments consist of lipid-rich biologic membranes. Lipid solubility governs the rate of diffusion of drugs across said membranes. Ionization reduces a drug’s lipid solubility

Question 4

Which route of administration will not allow drugs to undergo first-pass metabolism?
a.PO
b.Intraperitoneal
c. Intrarectal
d.Both A and B

Answer 4

Intrarectal

First pass metabolism usually occur in gastrointestinal segments drained by the portal vein. The portal vein
drains blood from the pancreas, the spleen, and the entire GI tract except the caudal rectum and the anal canal

Question 5

The following are the pharmacologic effects of epinephrine except:
a.Splenic Contraction
b.Increased force of cardiac myocyte contraction
c. Contraction of pilomotor muscles
d.Vasoconstriction at low doses

Answer 5

Vasoconstriction at low doses

Epinephrine produces vasodilation at low doses. At higher doses, it produces vasoconstriction

Question 6

In which gestating animal species is xylazine contraindicated:
a.Canines
b.Equines
c. Felines
d.Ruminants

Answer 6

Ruminants

When used in gestating cattle especially in the third trimester of pregnancy, xylazine may cause premature parturition

Question 7

What happens when sweat glands are stimulated through cholinergic receptors?
a.Secretions are increased
b.Secretions are decreased
c.Nothing happens
d.Sweat glands are not stimulated through cholinergic
receptors

Answer 7

Secretions are increased

Sweat glands are mainly under the sympathetic nervous system. The postganglionic neurons of the SNS use acetylcholine as their main neurotransmitter

Question 8

The following describe the desirable characteristics of a drug to allow it to cross the BBB except:
a.High lipid solubility
b.Small molecular size
c.Unbound to protein
d.The presence of inflammation

Answer 8

The presence of inflammation

Inflammation is not a drug characteristic

Question 9

This drug is often used with a local anesthetic to restrict its area of action and to prolong its effects
a.Styptics
b.Epinephrine
c.Atropine
d.Dopamine

Answer 9

Epinephrine

Epinephrine acts as a local vasoconstrictor. It also decreases the removal of the drug from the site of administration

Question 10

Among the following analgesics used in horses, which has the shortest duration of activity?
a.Flunixin Meglumine
b.Phenylbutazone
c. Carprofen
d.Ibuprofen

Answer 10

Phenylbutazone

Flunixin meglumine – 13 hrs
Carprofen – 12 hrs
Phenylbutazone – 8 hrs

Question 11

Which of the following does not describe isoflurane?
a. Isoflurane has a low blood-gas partition coefficient
b.It is the inhalant anesthetic of choice for patients with increased intracranial pressure
c. It should not be used in swine because it may cause malignant hyperthermia
d.It may be used in animals with liver disease

Answer 11

It should not be used in swine because it may cause malignant hyperthermia

Malignant hyperthermia is a pharmacogenetic myopathy involving a defect of the ryanodine receptor in the sarcoplasmic reticulum. All modern volatile agents including isoflurane, enflurane, sevoflurane, and desflurane can trigger this condition

Question 12

Drugs that affect the autonomic nervous system produce their effects by doing the following except:
a.Mimic the effect of neurotransmitters
b.Interfere with neurotransmitter release
c.Block the attachment of neurotransmitters to receptors
d.Assist with the uptake of neurotransmitters at the synapse

Answer 12

Assist with the uptake of neurotransmitters at the synapse

Sympatho- and parasympathomimetic drugs are agonists

Question 13

Which corticosteroid has a rapid onset and is short acting?
a. Dexamethasone
b.Prednisone
c. Flumethasone
d.Triamcinolone

Answer 13

Prednisone

Dexamethasone and triamcinolone are rapid onset intermediate acting drugs. Flumethasone is a slow onset, long acting drug

Question 14

Which of the following drugs is used to treat organophosphate toxicosis?
a.Propantheline
b.Scopolamine
c.Glycopyrrolate
d.Pralidoxime

Answer 14

Pralidoxime

Pralidoxime is a cholinesterase reactivator. The drug removes and binds the offending phosphoryl group attached to the enzyme, which is then excreted.

Question 15

Acetylcholinesterase agents prevent the hydrolysis of Ach. Which of the following is the MOA of organophosphates?
a.Acetylation
b.Carbamylation
c.Phosphorylation
d.NOTA

Answer 15

Phosphorylation

They act via phosphorylation. Phosphorylation generally causes irreversible inhibition of acetylcholinesterase

Question 16

Which of the following anticonvulsant drugs is the best choice to terminate on-going seizures?
a.Phenobarbital
b.Pentobarbital
c. Dichlorofention
d.Cefalexin

Answer 16

Pentobarbital

Pentobarbital acts rapidly. Although phenobarbital is an anticonvulsant, would take around 20-30 minutes to produce an effect even after parenteral administration

Question 17

The following drug families are non-selective COX inhibitors except:
a.Oxicams
b.Nicotinic acid
c.Acetic acid
d.Coxibs

Answer 17

Coxibs

Question 18

These are opioid receptors that predominate the cerebral cortex:
a.Mu
b.Kappa
c. Delta
d.Epsilon

Answer 18

Kappa

Mu receptors are located throughout the brain and the lamina I and II of the dorsal horn of the spinal cord. Delta Receptors are found in the limbic system. Kappa Receptors are found in the cerebral cortex and the spinal cord

Question 19

At the Alpha receptors, which of the following
drugs/neurotransmitters is the most potent?
a.Epinephrine
b.Norepinephrine
c. Dopamine
d.Isoprenaline

Answer 19

Norepinephrine

Norepinephrine binds only to three receptors namely: A1, A2, and B2. Epinephrine on the other hand, binds to four receptors.

Question 20

Which of the following animal species does not have a stable rate of gastric emptying?
a.Equines
b.Bovines
c. Canines
d.Ovines

Answer 20

Canines

Gastric emptying refers to the rate of drug delivery to the small intestine from the stomach. Carnivores are periodic eaters and have large swings in gastric pH

Question 21

Which of the following does not describe acepromazine?
a.Acepromazine is a Phenothiazine tranquilizer
b.It is extremely potent but the duration of activity is dose dependent
c. It may be used to treat malathion toxicosis
d.It may be given to animals exhibiting emesis

Answer 21

It may be used to treat malathion toxicosis

Acepromazine may potentiate the effects of organophosphates

Question 22

Which of the following statements regarding general anesthesia is incorrect?
a.General anesthesia usually results in a reversible
depression of the CNS
b.Anesthetics used to produce general anesthesia reduce and stop electrical activity of the brain and decrease O2
consumption
c.General anesthesia is induced by depositing the anesthetic agent in close proximity to a nerve membrane
d.General anesthesia is considered as a dose-related
continuum

Answer 22

General anesthesia is induced by depositing the anesthetic agent in close proximity to a nerve membrane

This refers to local anesthesia. The deposition of an anesthetic agent near a nerve membrane allows the blockage of nerve conduction

Question 23

Which of the following anesthetics lack analgesic properties?
a.Xylazine
b.Chloral hydrate
c.Tiletamine
d.Dexdetomidine

Answer 23

Chloral hydrate

A2 adrenergic agonists produce dose-related sedation and analgesia. Opioids produce potent analgesia and sedation

Question 24

Which of the following describes an impossible prescription?
a.The generic name of the drug is not written
b.The generic name is not legible and a brand name is
legibly written
c.The generic name is in parenthesis
d.When only the generic name is written but it is not
legible

Answer 24

When only the generic name is written but it is not legible

Choices A and B are classified as violative prescriptions. Choice C is classified as an erroneous prescription. DA AO No. 39 Series of 1991

Question 25

Which of the following statements does not accurately describe antagonists? a.These are drugs that block the response produced by an agonist b.Partial agonists may also serve as antagonists c.Antagonists can produce an effect on their own and therefore has intrinsic activity d.Antagonists have no intrinsic activity

Answer 25

Antagonists can produce an effect on their own and therefore has intrinsic activity Antagonists have no intrinsic activity. They can only block the action of specific endogenous ligands with affinity to the receptor

Question 26

Which of the following is not a property of a drug receptor? a.Saturability b.Specificity c.Reversibility d.None of the above

Answer 26

None of the above Saturability – Limited numbers of receptors present Specificity – Lock and key theory Reversibility – The drug that binds to a receptor can dissociate into its non-metabolized form

Question 27

Which of the following is not expressed by B2 receptors? a.Heart b.Urinary Bladder c. Liver d.Bronchial smooth muscles

Answer 27

Heart The heart is primarily expressed by B1 receptors

Question 28

It is an inducible enzyme formed at the site of inflammation and produces proinflammatory prostaglandins such as PGE2 a. LOX 1 b. LOX-2 c. COX-1 d. COX-2

Answer 28

COX-2 COX 1 is a constitutive enzyme that performs a range of housekeeping functions. Cyclooxygenase-2 is overexpressed in inflammatory tissue

Question 29

What is the treatment of choice for pigs suffering from fulmigant malignant hyperthermia? a.Azaperone b.Dantrolene c.Bezanepril d.Dexmedetomidine

Answer 29

Dantrolene Malignant hyperthermia is characterized by muscle rigidity, a rapid rise in body temperature, a large consumption of O2, and consequent production of CO2. Dantrolene acts directly on the muscles, interfering with calcium release

Question 30

Which of the following is the main determinant for animal recovery from inhalant anesthesia? a. Vapor Pressure b. Oil-Gas Partition coefficient c. Blood-Gas Partition Coefficient d. Molecular weight

Answer 30

Blood-Gas Partition Coefficient A low blood gas partition coefficient allows for more rapid anesthetic induction and a more rapid rate of recovery

Question 31

It refers to the introduction of drugs into the stomach via a tube or a needle a. Lavage b. Gavage c. Intraperitoneal d. Intrathecal

Answer 31

Gavage Lavage refers to washing an organ or a cavity with fluid

Question 32

A drug that has a concentration of 10 mg/ml has been administered via IV to a patient. Assuming that 2 ml of the drug has been given, how many mg will be absorbed? a. 10 mg b. 20 mg c. 5 mg d. 30 mg

Answer 32

20 mg Absorption refers to the total amount of drug that reaches the bloodstream. Bioavailability is a factor being considered to determine the amount of drug being absorbed. Intravenous administration offers 100% bioavailability

Question 33

Which of the following is not a pharmacologic effect of atropine? a. Inhibition of sweating and salivary secretions b. Decreases GI and urinary tract motility c. Pupillary constriction d. Inhibition of gastric secretions

Answer 33

Pupillary constriction At low doses, ATS inhibits salivation, bronchial secretions, and sweating. At moderate doses, ATS dilates and inhibits the accommodation of the pupils. High doses will reduce GI and urinary tract motility. Very high doses will inhibit gastric secretions

Question 34

Which of the following drugs is not an antimuscarinic agent? a. Atropine b. Glycopyrrolate c. Propantheline d. Carbachol

Answer 34

Carbachol Carbachol is a nicotinic receptor agonist

Question 35

In which animal species does propofol induce oxidative injuries? a. Feline b. Canine c. Bovine d. Ovine

Answer 35

Feline Propofol administration in cats can result in Heinz body formation, anorexia, diarrhea, and malaise.

Question 36

In terms of binding to plasma proteins, acidic drugs bind to_______, while basic drugs bind to________. a. Albumin:A1 acid glycoprotein b. Albumin: Lysine c. Lysine: Cysteine d. A1 acid glycoprotein: Albumin73

Answer 36

Albumin:A1 acid glycoprotein Plasma protein binding occur in the circulation and almost all drugs exhibit this phenomenon. Binding slows drug distribution. It may also affect the potency of the drug.

Question 37

What is the oxidation product of epinephrine after prolonged exposure to heat and light? a. Carbazenochrome b. Adrenochrome c. Catechol-o-methyltransferase d. Synephrine

Answer 37

Adrenochrome Occur after prolonged exposure of epinephrine in heat or light and is initially pink in appearance. It may later turn brown after further oxidation.

Question 38

Barbiturates have been used to control seizures. What is their MOA? a. Competitively bind with muscarinic receptors b. Increase the release of enkephalins c. Increase the concentration of cholinesterases d. Potentiation of GABA

Answer 38

Potentiation of GABA Potentiate GABA. They may also inhibit the release of excitatory neurotransmitters

Question 39

Which of the following barbiturates is the drug of choice for the long-term treatment of seizures? a. Phenobarbital b. Pentobarbital c. Phenytoin d. Thiamylal

Answer 39

Phenobarbital Phenobarbital limits the spread of action potentials and elevates seizure threshold. It cannot terminate ongoing seizures

Question 40

Which of the following is not a pharmacologic effect of opioids? a. Analgesia b. Respiratory depression c. Histamine release d. Increase GI motility

Answer 40

Increase GI motility Opioids lower GI motility. Anti-diarrheal effects are produced upon stimulation of Mu and Kappa receptors

Question 41

Fentanyl is mixed with which drug to achieve neuroleptanalgesia? a. Azaperone b. Oxymorphone c. Droperidol d. Diazepam

Answer 41

Droperidol Neuroleptnalagesia is achieved by adding fentanyl and droperidol (0.4 mg/ml and 2 mg/ml respectively)

Question 42

Which of the following statements is not true? a. All drugs must pass through cell membranes to reach their receptors b. A thicker cell membrane negatively impacts drug passage c. Only the nonionized fraction of the drug diffuses through lipid membranes d. None of the above

Answer 42

All drugs must pass through cell membranes to reach their receptors Not all drugs need to pass through cell membranes. Aqueous pores in lipoproteinaceous biologic membranes offer a means of xenobiotic movement through the membrane for predominantly aqueous drugs

Question 43

What enzyme is largely responsible for Phase I of drug biotransformation? Question 44 Board Review 2024 www.myboardprep.org #VMLE2024 a. Monoamine oxidase b. Gulonolactone oxidase c. Cytochrome P450 d. Glucuronyl transferase

Answer 43

Cytochrome P450 Cytochrome P450 (CYP) is a hemeprotein that plays a key role in the metabolism of drugs and other xenobiotics. The most common phase I reaction is oxidation and is mainly catalyzed by said enzyme.

Question 44

Conversion of enalapril to enalaprilat is an example of which sequela of biotransformation? a. Inactivation b. Activation c. Modification of activity d. Lethal synthesis

Answer 44

Activation Enalaprilat is the active compound of enalapril and is mainly converted in the liver. Enalaprilat prevents the formation of angiotensin II.

Question 45

The following statements regarding drug metabolism is true except: a. Majority of drug metabolism occur in the SER of the liver b. Increase in plasma albumin may indicate a decrease in hepatic drug metabolism c. Hyperthyroidism may increase the rate of drug metabolism d. Ornithine conjugation occur in reptiles and birds

Answer 45

Increase in plasma albumin may indicate a decrease in hepatic drug metabolism A decrease in plasma albumin may indicate an ongoing hepatic disease. Hepatic disease states in general, may decrease the rate of drug metabolism

Question 46

The following statements regarding drug excretion are incorrect except: a. Acidification or alkalinization of urine has no effect on drug excretion b. The liver is the principal organ for drug excretion c. Cardiac output can influence the rate of drug excretion d. None of the above

Answer 46

Cardiac output can influence the rate of drug excretion Renal excretion is highly dependent on renal blood flow. Renal blood flow in turn is highly influenced by the cardiac output

Question 47

What type of drug antagonism occurs when doxycycline interacts with milk? a. Chemical antagonism b. Physiologic antagonism c. Pharmacokinetic antagonism d. Pharmacologic antagonism 95

Answer 47

Chemical antagonism Chelation occurs which results to inactivation of doxycyline

Question 48

Which of the following epidermal layers effectively acts as a barrier against drug diffusion into the circulation? a. Stratum basale b. Stratum spinosum c. Stratum lucidum d. Stratum corneum

Answer 48

Stratum corneum

Question 49

Which of the following statements regarding topical administration is correct? a. Drugs applied at the palmar and the plantar regions are absorbed more readily compared to other skin regions b. The skin of horses are used to directly compare the rate of absorption to human skin c. The inner ear is an excellent area for drug absorption d. Cutaneous blood flow does not play a factor in drug absorption

Answer 49

The inner ear is an excellent area for drug absorption Palmar and plantar regions are highly cornified. Primates and pigs are used for human approximation