PHARMACOLOGY Sample Questions 2 Flashcards
Two drugs, A and B, have the same mechanism of action. Drug A in a dose of 5 mg. produces the same magnitude of response as drug B in a dose of 500 mg. Which of the following statements is correct?
a. Drug A is less toxic
b. Drug A is more efficacious
c. Drug A is 100 times as potent
d. Drug A has a shorter duration of action
e. Drug A is a better drug to use when a maximal response is desired
C
According to the theory that agonists and antagonists occupy the same receptor site, an effective antagonist should exhibit
a. High intrinsic activity and high affinity
b. Low intrinsic activity and low affinity
c. High intrinsic activity and low affinity
d. No intrinsic activity and high affinity
D
All of the following statements are true regarding the occupation theory of drug-receptor interaction EXCEPT:
a. The affinity of a drug is dependent on its intrinsic activity
b. The maximum effect of a drug occurs when all receptors are occupied
c. An antagonist has affinity for the receptor but not intrinsic activity
d. The magnitude of the effect of a drug is proportional to the number of receptors occupied
e. It follows the law of mass action
A
The occupational theory of drug-receptor interaction states that
a. The magnitude of the drug response is proportional to the number of receptors occupied
b. A partial agonist has intrinsic activity but no affinity for the receptor site
c. An antagonist drug has affinity but no intrinsic activity
d. The rate at which the drug-receptor complex associates and dissociates determines drug efficacy
e. The degree of drug action is dependent on the law of mass action
i. (a), (b) and (c)
ii. (a), (c) and (e)
iii. (b), (c) and (d)
iv. (b) and (e)
v. (c), (d) and (e)
ii
Diazepam is preferred to a barbiturate as an antianxiety agent because diazepam
a. Produces no sedation
b. Has less addiction potential
c. Is a very short-acting drug
d. Is substantially less expensive
e. Does not potentiate the action of CNS depressants
B
Benzodiazepines produce their antianxiety effects by modulating which of the following neurohumors?
a. GABA
b. Glycine
c. Dopamine
d. Acetylcholine
e. Norepinephrine
A
Benzodiazepines exert their main effect on
a. Neuromuscular junctions
b. Peripheral reflex synapses
c. Central GABAergic neurons
d. Central serotonergic neurons
e. Central adrenergic nerve endings
C
All of the following pertain to general anesthesia induced by thiopental EXCEPT:
a. Fast induction
b. Decreased secretions
c. Low therapeutic index
d. Short duration of anesthesia
e. Predisposition to laryngospasm
B
Which of the following factors contributes to the short duration of action of a single dose of thiopental?
a. rapid biotransformation
b. rapid accumulation in body fat
c. high lipid solubility of the undissociated form
d. ability to enter and leave the brain tissue rapidly
D
Speed of recovery from short-acting anesthesia with thiopental depends chiefly on the rapidity of
a. Renal tubular secretion
b. Hepatic degradation of the thiopental group
c. Redistribution from the brain to skeletal muscle
d. Reverse diffusion across the blood-brain barrier
e. None of the above
C
The action of the ultrashort-acting barbiturates is terminated primarily by the process of a. Oxidation b. Redistribution c. Renal excretion d. Plasma protein binding e. Conjugation with sulfate
B
Which of the following is NOT characteristic of barbiturates?
a. Possess anticonvulsant properties
b. Possess significant analgesic properties
c. Possess serious drug dependence potential
d. Vary in degree of lipid solubility and hypnotic potency
B
The cause of death from acute barbiturate poisoning is
a. Convulsions
b. Liver damage
c. Renal failure
d. Respiratory failure
e. Cardiovascular depression
D
Which of the following adverse effects is most commonly associated with administration of an intravenous barbiturate?
a. Hypotension
b. Renal failure
c. Hepatic necrosis
d. Nausea and vomiting
e. Respiratory depression
E
Important steps in the treatment of barbiturate poisoning include:
a. Maintaining an open airway
b. Increasing the input of afferent stimuli
c. Maintaining respiration
d. Administering a narcotic antagonist
e. Administering a central nervous system stimulant
i. (a) and (b) only
ii. (a), (b), (c) and (e)
iii. (a) and (c) only
iv. (b) and (e) only
v. (d) only
ii
Which of the following are true regarding barbiturates?
a. Significantly elevates pain thresholds
b. Are metabolized by the liver
c. Are classified according to duration of action
d. Depress all levels of the CNS
e. Cause death by cardiovascular depression
i. (a), (b) and (c)
ii. (a) and (d)
iii. (b), (c) and (d)
iv. (b) and (e)
v. (c), (d) and (e)
iii
Barbiturates are contraindicated in a dental patient with:
a. Emphysema
b. Hypertension
c. Undiagnosed severe pain
d. Acute intermittent porphyria
i. (a), (c) and (d)
ii. (a) and (d) only
iii. (b) and (c)
iv. (b) only
i
If diazepam (Valium) is to be given intravenously, it is recommended
that a large vein be used in order to
a. Hasten the onset of action
b. Decrease the risk of thrombophlebitis
c. Offset the vasoconstrictor qualities of diazepam
d. None of the above
B
The most important therapeutic measure to be taken in a case of barbiturate poisoning is to
a. Alkalinize the urine
b. Aspirate stomach contents
c. Administer a CNS stimulant
d. Assure adequate respiration
e. Administer osmotic diuretics
D
For oral sedation in the dental setting, the most ideal group of agents is:
a. Narcotics
b. Barbiturates
c. Antihistamines
d. Benzodiazepines
e. Anticholinergics
D
Which of the following is an advantage of midazolam over diazepam EXCEPT one. Which one is this EXCEPTION?
a. Lesser incidence of thrombophlebitis
b. Shorter elimination half-life
c. No significant active metabolites
d. Less potential for respiratory depression
e. More rapid and predictable onset of action when given intramuscularly
D
Which of the following drugs best reverses the effects of benzodiazepines?
a. Naloxone
b. Flumazenil
c. Midazolam
d. Aminophylline
e. Physostigmine
B
Which of the following are pharmacologic properties of antipsychotic drugs?
a. They block the dopamine receptor
b. They affect the hypothalamic temperature regulation system
c. They cause emesis
d. They are synergistic with LSD
e. They cause hypertension
i. (a) and (b) only
ii. (a), (b) and (c)
iii. (b), (c) and (d)
iv. (c), (d) and (e)
v. (d) and (e) only
i
The antipsychotic effects of the phenothiazines are probably the result
of
a. Release of serotonin in the brain
b. Release of norepinephrine in the brain
c. Blockade of dopaminergic sites in the brain
d. Prevention of the release of norepinephrine from brain neuron
terminals
e. Increase in the dopamine content of the cerebral cortex
C
The antipsychotic effects of phenothiazines result from
a. Release of serotonin in the brain
b. Release of norepinephrine in the brain
c. Blockade of dopaminergic sites in the brain
d. An increase in the dopamine content of the cerebral cortex
e. Prevention of the release of norepinephrine from brain neuron
terminals
C
Chlorpromazine and related drugs are thought at act by blocking which of the following receptors?
a. Adrenergic
b. Muscarinic
c. Dopaminergic
d. Central serotonin
C
Which of the following is an irreversible side-effect resulting from long-term administration of phenothiazines?
a. Sedation
b. Xerostomia
c. Infertility
d. Parkinsonism
e. Tardive dyskinesia
E
Tardive dyskinesia is a neurological side-effect of which of the following classes of drugs?
a. Alcohols
b. Tricyclic antidepressants
c. Barbiturate antiepileptics
d. Phenothiazine antipsychotics
e. Monoamine oxidase inhibitors
D
Which of the following drugs are most likely to cause extrapyramidal stimulation?
a. Antibiotics
b. Salicylates
c. Barbiturates
d. Phenothiazines
e. Benzodiazepines
D
Phenothiazine derivatives do NOT produce
a. Jaundice
b. Xerostomia
c. Gingival hyperplasia
d. Postural hypotension
e. Symptoms of parkinsonism
C
All of the following actions are associated with the use of chlorpromazine EXCEPT:
a. Jaundice
b. Photosensitivity
c. Excessive salivation
d. Anticholinergic effects
e. Antiadrenergic effects
C
The drug most commonly used to treat severe mental depression is
a. Sodium
b. Imipramine
c. Chlorpromazine
d. Tranylcypromine
e. Dextroamphetamine
B
Which of the following drugs is most effective as an antidepressant?
a. Diazepam
b. Reserpine
c. Amitriptyline
d. Chlorpromazine
e. Hydroxyzine
C
Which of the following is most likely to be the major mechanism of action of the tricyclic antidepressants?
a. Enhanced release of acetylcholine
b. Inhibition of neuronal synthesis of norepinephrine
c. Potentiation of serotonin synthesis in nervous tissue
d. Stimulation of reuptake of norepinephrine from the synaptic cleft
e. Blockade of the reuptake of amine neurotransmitters released into the synaptic cleft
E
Tricyclic antidepressants have a prominent side effect that most nearly resembles the usual pharmacological action of
a. Codeine
b. Atropine
c. Ephedrine
d. Propranolol
e. Methacholine
B
Which of the following drugs has its primary use in the treatment of the manic phase of depressive psychosis?
a. Lithium
b. Reserpine
c. Imipramine
d. Amphetamine
e. Chlorpromazine
A
Lithium carbonate is particularly effective in treating
a. Parkinsonism
b. Hypertension
c. Schizophrenia
d. Acute anxiety
e. Manic-depressive psychosis
E
The current drug of choice for treatment of the manic phase of manic-depressive psychosis is
a. Lithium
b. Caffeine
c. Reserpine
d. Imipramine
e. Amphetamine
A
Which of the following statements is NOT true regarding the adrenal corticosteroids?
a. Cause retention of sodium and fluid
b. Decrease activity in lymphoid tissue
c. Heighten the immune response to antigens
d. Can produce a diabetes-like syndrome with high blood levels
e. Are therapeutically beneficial when administered orally, parenterally or topically
C
Which of the following conditions contraindicate use of corticosteroids in a dental patient?
a. AIDS
b. Candidiasis
c. Tuberculosis
d. Peptic ulcers
i. (a), (b) and (c)
ii. (a), (b) and (d)
iii. (b), (c) and (d)
iv. (c) and (d) only
v. All of the above
v
Which of the following does NOT result from prolonged treatment with steroids?
a. Gastric ulcer
b. Osteoporosis
c. Hyperglycemia
d. Myocardial atrophy
e. Redistribution of body fat
D
Glucocorticosteroids are useful as secondary treatment of anaphylaxis because they
a. Inhibit the production of antibodies
b. Prevent the union of antigen with antibody
c. Prevent the release of histamine from sensitized cells
d. Suppress the inflammatory response to cell injury
e. Inhibit the release of serotonin from vascular storage sites
D
Adrenal steroids are used successfully to treat all of the following conditions EXCEPT
a. Gastric ulcers
b. Addison disease
c. Lupus erythematosus
d. Rheumatoid arthritis
e. Aphthous stomatitis
A
Signs and stages of anesthesia are most likely to be seen with a general anesthetic that has a
a. Low potency
b. Slow rate of induction
c. Low Ostwald coefficient
d. High oil-water solubility coefficient
e. High tissue-blood partition coefficient
B
All of the following influence the rate of induction during anesthesia EXCEPT:
a. Pulmonary ventilation
b. Blood supply to the lungs
c. Hemoglobin content of the blood
d. Concentration of the anesthetic in the inspired mixture
e. Solubility of the anesthetic in blood (blood-gas partition coefficient, Ostwald coefficient).
C
The rapidity of onset of anesthesia with an inhalation anesthetic agent is primarily related to its
a. Molecular weight
b. Degree of blood solubility
c. Temperature in the gas phrase
d. Interaction with preoperative drugs
B
Which of the following forms of drug toxicity is associated with the halogenated hydrocarbon general anesthetics?
a. Liver damage
b. Myocardial atrophy
c. Peripheral neuritis
d. Severe hypertension
A
The behavior of patients under general anesthesia suggests that the most resistant part of the central nervous system is the
a. Spinal cord
b. Medulla oblongata
c. Cerebral cortex (motor area)
d. Cerebral cortex (sensor area)
B
General anesthetics can do all of the following EXCEPT:
a. Produce delirium
b. Stimulate medullary centers
c. Produce a state of unconsciousness
d. Reduce perception of painful stimuli
e. Decrease excitability of the motor cortex
B
In general anesthesia, the last part of the CNS to be depressed is the
a. Medulla
b. Cerebrum
c. Midbrain
d. Cerebellum
e. Spinal cord
A
General anesthesia with halothane is commonly preceded by administration of atropine to
a. inhibit vagal overactivity commonly caused by halothane
b. induce muscular relaxation by blocking cholinergic receptors
c. reduce salivation and bronchial secretions caused by halothane
d. all of the above.
C
Which of the following drugs is useful in treating dermatologic manifestations of an allergic response?
a. Diazepam
b. Atropine
c. Hexylresorcinol
d. Chlorpheniramine
e. Phenoxybenzamine
D
Cimetidine is used therapeutically to
a. Stimulate respiration
b. Protect against anaphylaxis
c. Decrease gastric acid secretion
d. Hasten excretion of barbiturates
e. Dilate smooth muscles of the bronchioles
C
Gastric acid secretion has been shown to be most effectively reduced with the use of
a. Adrenal steroids
b. Anticholinergic drugs
c. Serotonin antagonists
d. H1-histamine receptor antagonists
e. H2-histamine receptor antagonists
E
Drug-mediated inhibition of H2-histamine receptors is most useful in treating
a. Asthma
b. Anaphylaxis
c. Contact dermatitis
d. Gastric hyperacidity
e. Localized allergic reactions
D
Which of the following antihistamines is most commonly used as preoperative medication? a. Meclizine
b. Cyclizine
c. Promethazine
d. Dimenhydrinate
e. Chlorpheniramine
C
Use of diphenhydramine (Benadryl ) in controlling the symptoms of parkinsonism is based upon which of the following effects?
a. Anticholinergic
b. Local anesthetic
c. Adrenergic-blocking
d. CNS depressant on the midbrain
e. Stimulant to dopaminergic nerves in the basal ganglia
A
The mechanism of action of H1 antihistamines is
a. MAO enzyme inhibition
b. competitive antagonism
c. physiologic antagonism
d. noncompetitive antagonism
e. inhibition of release of bound histamine
B
which of the following drugs is often used to treat trigeminal neuralgia? A. clonazepam B. carbamazepine C. acetazolamine D. succinylcholine
B
the use of epinephrine for local hemostasis during surgery might result in A. hypoglycemia B. cardiac arrhythmia C. an acute asthma attack D. a drastic drop in BP E. any of the above
B
the highest risk associated with use of oral contraceptives is A. hepatic necrosis B. permanent sterility C. cancer of the breast D. cancer of the uterus E. thromboembolic disorders
E
factors common to all forms of drug abuse include A. miosis B. tolerance C. physical dependence D. psychological dependence E. any of the above
D
alcoholic euphoria results from
A. increased activity of the cerebellum
B. increased activity of the cerebral areas
C. increased activity of the spinal synapses
D. decreased activity of the medullary centers
E. removal of inhibitory activity of the cortex
E
sulfonylureas cause insulin secretion by
A. adrenergic stimulation
B. cholinergic stimulation
C. direct stimulation of pancreatic beta cells
C
if a patient requiring an extraction reports that he is on dicoumarol therapy, the laboratory test most valuable in evaluating the surgical risk is A. clotting time B. bleeding time C. sedimentation rate D. complete blood cell count E. plasma prothrombin time
E
a drug has a half-life of 4 hours. if 2g are given every 4 hrs, what will be the amount in grams in the body immediately after the third dose? A. 1.5 B. 2.0 C. 3.5 D. 4.0 E. 6.0
C
which of the following combinations represents acceptable agonist-antagonist pairs in antidotal therapy? A. morphine-naloxone B. dicoumarol-protamine C. warfarin-phenylbutazone D. carbon monoxide-carbon dioxide
A
The various insulin preparations useful in the treatment of diabetes mellitus differ primarily in
a. locus of action
b. mechanism of action
c. mode of transformation
d. onset and duration of action
e. none of the above
D
Displacement of a drug from protein binding sites is expected to increase the
a. drug effect observed
b. duration of drug effect
c. dose required for a given effect
d. none of the above
A
In an addisonian crisis (hypoaldosteronism) resulting from stress from a minor dental procedure, the patient should be treated immediately with
a. 0.5 ml norepinephrine
b. 5 mg. prednisolone acetate
c. 1% triamcinolone acetonide
d. 0.5 ml, 1:1000 epinephrine
e. 2 ml (100 mg) hydrocortisone hemisuccinate
E
Drug A inhibits the biotransformation of Drug B. The duration of action of drug B in the presence of drug A will usually be
a. shortened
b. prolonged
c. unchanged
B