Veterinary Pharma - General Pharmacology B Flashcards
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
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
Which of the following processes is not a part of the Phase 1 of biotransformation?
a.Oxidation
b.Acetylation
c. Hydrolysis
d.Reduction
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
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
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
Which route of administration will not allow drugs to undergo first-pass metabolism?
a.PO
b.Intraperitoneal
c. Intrarectal
d.Both A and B
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
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
Vasoconstriction at low doses
Epinephrine produces vasodilation at low doses. At higher doses, it produces vasoconstriction
In which gestating animal species is xylazine contraindicated:
a.Canines
b.Equines
c. Felines
d.Ruminants
Ruminants
When used in gestating cattle especially in the third trimester of pregnancy, xylazine may cause premature parturition
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
Secretions are increased
Sweat glands are mainly under the sympathetic nervous system. The postganglionic neurons of the SNS use acetylcholine as their main neurotransmitter
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
The presence of inflammation
Inflammation is not a drug characteristic
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
Epinephrine
Epinephrine acts as a local vasoconstrictor. It also decreases the removal of the drug from the site of administration
Among the following analgesics used in horses, which has the shortest duration of activity?
a.Flunixin Meglumine
b.Phenylbutazone
c. Carprofen
d.Ibuprofen
Phenylbutazone
Flunixin meglumine – 13 hrs
Carprofen – 12 hrs
Phenylbutazone – 8 hrs
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
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
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
Assist with the uptake of neurotransmitters at the synapse
Sympatho- and parasympathomimetic drugs are agonists
Which corticosteroid has a rapid onset and is short acting?
a. Dexamethasone
b.Prednisone
c. Flumethasone
d.Triamcinolone
Prednisone
Dexamethasone and triamcinolone are rapid onset intermediate acting drugs. Flumethasone is a slow onset, long acting drug
Which of the following drugs is used to treat organophosphate toxicosis?
a.Propantheline
b.Scopolamine
c.Glycopyrrolate
d.Pralidoxime
Pralidoxime
Pralidoxime is a cholinesterase reactivator. The drug removes and binds the offending phosphoryl group attached to the enzyme, which is then excreted.
Acetylcholinesterase agents prevent the hydrolysis of Ach. Which of the following is the MOA of organophosphates?
a.Acetylation
b.Carbamylation
c.Phosphorylation
d.NOTA
Phosphorylation
They act via phosphorylation. Phosphorylation generally causes irreversible inhibition of acetylcholinesterase
Which of the following anticonvulsant drugs is the best choice to terminate on-going seizures?
a.Phenobarbital
b.Pentobarbital
c. Dichlorofention
d.Cefalexin
Pentobarbital
Pentobarbital acts rapidly. Although phenobarbital is an anticonvulsant, would take around 20-30 minutes to produce an effect even after parenteral administration
The following drug families are non-selective COX inhibitors except:
a.Oxicams
b.Nicotinic acid
c.Acetic acid
d.Coxibs
Coxibs
These are opioid receptors that predominate the cerebral cortex:
a.Mu
b.Kappa
c. Delta
d.Epsilon
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
At the Alpha receptors, which of the following
drugs/neurotransmitters is the most potent?
a.Epinephrine
b.Norepinephrine
c. Dopamine
d.Isoprenaline
Norepinephrine
Norepinephrine binds only to three receptors namely: A1, A2, and B2. Epinephrine on the other hand, binds to four receptors.
Which of the following animal species does not have a stable rate of gastric emptying?
a.Equines
b.Bovines
c. Canines
d.Ovines
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
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
It may be used to treat malathion toxicosis
Acepromazine may potentiate the effects of organophosphates
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
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
Which of the following anesthetics lack analgesic properties?
a.Xylazine
b.Chloral hydrate
c.Tiletamine
d.Dexdetomidine
Chloral hydrate
A2 adrenergic agonists produce dose-related sedation and analgesia. Opioids produce potent analgesia and sedation
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
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
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
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
Which of the following is not a property of a drug receptor?
a.Saturability
b.Specificity
c.Reversibility
d.None of the above
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
Which of the following is not expressed by B2 receptors?
a.Heart
b.Urinary Bladder
c. Liver
d.Bronchial smooth muscles
Heart
The heart is primarily expressed by B1 receptors
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
COX-2
COX 1 is a constitutive enzyme that performs a range of
housekeeping functions. Cyclooxygenase-2 is overexpressed in inflammatory tissue
What is the treatment of choice for pigs suffering from fulmigant malignant hyperthermia?
a.Azaperone
b.Dantrolene
c.Bezanepril
d.Dexmedetomidine
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
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
Blood-Gas Partition Coefficient
A low blood gas partition coefficient allows for more rapid anesthetic induction and a more rapid rate of recovery
It refers to the introduction of drugs into the stomach via a tube or a needle
a. Lavage
b. Gavage
c. Intraperitoneal
d. Intrathecal
Gavage
Lavage refers to washing an organ or a cavity with fluid
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
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
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
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
Which of the following drugs is not an antimuscarinic agent?
a. Atropine
b. Glycopyrrolate
c. Propantheline
d. Carbachol
Carbachol
Carbachol is a nicotinic receptor agonist
In which animal species does propofol induce oxidative injuries?
a. Feline
b. Canine
c. Bovine
d. Ovine
Feline
Propofol administration in cats can result in Heinz body formation, anorexia, diarrhea, and malaise.
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
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.
What is the oxidation product of epinephrine after prolonged exposure to heat and light?
a. Carbazenochrome
b. Adrenochrome
c. Catechol-o-methyltransferase
d. Synephrine
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.
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
Potentiation of GABA
Potentiate GABA. They may also inhibit the release of
excitatory neurotransmitters
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
Phenobarbital
Phenobarbital limits the spread of action potentials and elevates seizure threshold. It cannot terminate ongoing seizures
Which of the following is not a pharmacologic effect of opioids?
a. Analgesia
b. Respiratory depression
c. Histamine release
d. Increase GI motility
Increase GI motility
Opioids lower GI motility. Anti-diarrheal effects are produced upon stimulation of Mu and Kappa receptors
Fentanyl is mixed with which drug to achieve neuroleptanalgesia?
a. Azaperone
b. Oxymorphone
c. Droperidol
d. Diazepam
Droperidol
Neuroleptnalagesia is achieved by adding fentanyl and droperidol (0.4 mg/ml and 2 mg/ml respectively)
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
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
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
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.
Conversion of enalapril to enalaprilat is an example of which sequela of biotransformation?
a. Inactivation
b. Activation
c. Modification of activity
d. Lethal synthesis
Activation
Enalaprilat is the active compound of enalapril and is mainly converted in the liver. Enalaprilat prevents the
formation of angiotensin II.
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
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
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
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
What type of drug antagonism occurs when doxycycline interacts with milk?
a. Chemical antagonism
b. Physiologic antagonism
c. Pharmacokinetic antagonism
d. Pharmacologic antagonism 95
Chemical antagonism
Chelation occurs which results to inactivation of doxycyline
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
Stratum corneum
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
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
