ans_pd_pk-ans

8/2/2019 ANS_PD_PK-Ans

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1) A 45-year-old unemployed man was rushed to the hospital emergency room with symptomsof agitation, palpitations and profuse sweating. Physical examination revealed mydriasis,increased heart rate and blood pressure. History suggestive of amphetamine abuse. Whichamong the following statements best explains the reason for an increase in the heart rate inthis patient?

A) Amphetamine directly increasing cAMP levelsB) Amphetamine directly increasing IP3-DAG levelsC) Amphetamine causing a reflex increasing the heart rateD) Amphetamine indirectly increasing cAMP levelsE) Amphetamine indirectly increasing IP3-DAG levels

2) In the management of hypertension, if you want to choose a drug which would affect both thecardiac output and total peripheral resistance, which among the following drugs would youchoose?

A) AtenololB) PropranololC) MetoprololD) CarvedilolE) Prazosin

3) An investigational drug is being tested for its effects on the blood pressure in an anesthetizedmammal. The graph below shows the effect of drug administration on the blood pressure andthe heart rate. The arrow mark on the graph corresponds to the time of drug administration.Which among the following drug Vsmechanism of action would be most similar to the actions

of this investigational drug?

A) Ephedrine : Decreasing the IP3-DAG levels


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B) Phenylephrine : Increasing the IP3-DAG levelsC) Prazosin : Decreasing the IP3-DAG levelsD) Isoproterenol : Decreasing the cAMP levelsE) Propranolol : Decreasing the cAMP levels

4) The graph below represents the action of norepinephrine (NE) alone (curve B) andnorepinephrine (NE) in the presence of other drugs (curves A, C and D). Which among thefollowing statements is true with regard to the graph shown below?

A) Curve A represents NE in the presence of prazosinB) Curve A represents NE in the presence of phenoxybenzamineC) Curve C represents NE in the presence of CocaineD) Curve D represents NE in the presence of PhenoxybenzamineE) Curve D represents NE in the presence of prazosin

5) The ED50 values for cardiac stimulation and vascular smooth muscle relaxation of a newadrenergic agonist and epinephrine is shown below. From the data in the table below identifythe drug, which has the same characteristics as the new agonist?

A) IsoproterenolB) TerbutalineC) PropranololD) AmphetamineE) Xylometazoline


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6) The following graph shows the phenomena of tachyphylaxis exhibited by frequentadministration of ephedrine. Which among the following statements best explains themechanism behind the reduction in the hypertensive response to repeated injections ofephedrine?

A) Increased metabolism of ephedrineB) Increased availability of neurotransmitter in the synaptic cleftC) Downregulation of sympathetic receptorsD) Upregulation of sympathetic receptors

E) Depletion of neurotransmitter from the presynaptic nerve terminal

7) The following graph depicts the dose-response relationship of four different agonists namelyW, X, Y and Z. All four drugs act on the same receptor to produce this response. With respectto the following graph, identify the TRUE statement among the following:

A) Drug W has the highest ED50B) Drug W has the highest EmaxC) Drug Z has the lowest EmaxD) Drug Y is a partial agonistE) Drugs W, X and Y have the same ED50


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8) Drug X is given to a 25-year-old normal subject. This drug when given alone causes restingheart rate to increase from 62/min to 74/min. In the absence of the drug, the subjects heartrate increased to 150/min with vigorous exercise. After administration of drug X, the sameintensity of vigorous exercise caused his heart rate to increase only to 98/min. Which amongthe following drugs was given to this individual?

A) PindololB) MetoprololC) PhenoxybenzamineD) AtenololE) Prazosin

9) The following graph shows the effect of the drug administration on the end organs. The arrowmark corresponds to the time of drug administration. From the choices below identify the drug

A) Phenylephrine :B) IsoproterenolC) Dopamine :D) Ephedrine :E) Norepinephrine :

10) A 30-year-old woman with depression and mild hypertension is on a Monoamine oxidaseinhibitor (MAO-inhibitor). On the day of the event, in an office party, she had four big slices ofpizza with extra cheese. Soon after the event she complained of severe palpitations andheadache. She was rushed to the nearby hospital where her blood pressure was recorded as180/100 mm Hg. What is the mechanism behind the increase in blood pressure in thispatient?

A) Activation of receptors by tyramine in cheese

B) Activation of receptors by tyramine in cheeseC) Displacement of norepinephrine from presynaptic nerve terminalD) Displacement of epinephrine from presynaptic nerve terminalE) Displacement of dopamine from presynaptic nerve terminal


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11) A 45-year-old man is on propranolol for his hypertension. The following graph shows theeffect of various antihypertensive drugs on serum lipid levels (Triglycerides, LDL and HDLrespectively). Which among the following graphs would show the consequence of propranololtherapy in this patient?

A) Graph AB) Graph BC) Graph CD) Graph D

12) The graph below shows the log dose responses with norepinephrine in the absence andpresence of different drugs. If drug X is norepinephrine, then drug Y isA) Atropine

B) CocaineC) NeostigmineD) PrazosinE) None of the above

13) A 56-year-old woman is rushed to the ER by her relatives, who claim that the woman hadingested 10 tablets of her antihypertensive medication. The woman seems to be fullyconscious, but drowsy and exhausted. Her blood pressure is 60/40 mm Hg and her heart rateis 35 beats per minute. Which among the following drug was most likely taken by this patient?

A) Prazosin

X + Y


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B) PropranololC) LosartanD) EnalaprilE) Isoproterenol

14) The figure depicts the dose-response curve when norepinephrine is given alone and when itis given in the presence of a fixed dose of drug Y. Drug Y elicits no response when it is givenalone. The experimental system is an organ bath that contains a piece of vascular smoothmuscle. Drug Y in the figure is:

A) Phenoxybenzamine binding irreversibly to receptorsB) Prazosin binding irreversibly to receptors

C) Isoproterenol binding reversibly to receptors

D) Tamsulosin binding reversibly to receptors

E) Phenoxybenzamine binding reversibly to receptors

15) You are considering isoproterenol for a patient with bronchial asthma to inducebronchodilation. Which among the following adverse effect will limit the use of isoproterenol inthis otherwise healthy and non-pregnant patient?

A) Severe hypertensionB) TachycardiaC) CycloplegiaD) Excessive salivationE) Uterine relaxation

16) A 56-year-old man has been diagnosed with severe hypertension and is considered for

treatment with prazosin. Which among the following major physiological factor is affected byprazosin?

A) Central venous toneB) Peripheral vascular resistanceC) Cardiac contractilityD) Venous returnE) Blood volume


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17) A test drug enters the preclinical phase of drug trial and the safety of the drug is determined in

lab animals. The ED50 of the drug is identified as 10 g and the LD50 is identified as 1.0 Mg.What would be the therapeutic index of the drug?

A) 10

B) 1C) 100D) 1000E) 0.001

18) A 49-year-old man was diagnosed with severe hypertension and is considered for treatmentwith clonidine. Which among the following mechanism of action of clonidine would beresponsible for its hypotensive effect?

A) Stimulation of 1 receptors and increasing the IP3-DAG

B) Blockade of 1 receptors and decreasing the IP3-DAG

C) Stimulation of 2 receptors and decreasing cAMPD) Blockade of 2 receptors and increasing cAMP

E) Blockade of receptors and decreasing cAMP

25)A 35 year old known asthmatic patient after cholecystectomy couldnt pass flatus and stoolfor next 48 hours. To treat this paralytic ileus, pilocarpine was given. After some time patientdeveloped severe bronchospasm and becomes breathless. Underlying mechanism forbronchospasm seen in this patient is

A) Binding of Pilocarpine to M2 receptors

B) Pilocarpine blocking beta-2 receptorsC) Increase in adenylyl cyclaseD) Increase in IP-3 and DAGE) Pilocarpine binding to a receptor coupled to Gs protein

26) A 20 year old woman has myasthenia gravis. She doesnt have any acute effects. She hasvisited your clinic for followups. Which of the following drugs is most appropriate formaintenance therapy?

A) BethanecholB) Edrophonium

C) PilocarpineD) PralidoximeE) Pyridostigmine


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27) If curve C represents the increase of motility of isolated stomach after acetylcholine wasadministered alone, which curve represents the effect of acetylcholine in a preparationpretreated with physostigmine?

A) Curve AB) Curve CC) Curve DD) Curve EE) None of the above

28) A 48 year old farmer is brought to ER because of diarrhea , wheezing, agitation anddyspnea. On examination lacrimation, sweating, excess salivation, miosis and fasciculationof voluntary muscles was evident. Atropine and pralidoxime are administered to thispatient. Which of the following statement is true about his therapy?

A) Atropine is given to reverse the CNS effectsB) Pralidoxime acts by inhibiting the enzymeC) Blockade of Muscarinic receptors most likely to benefit the patientD) Blocking of Nicotinic receptors benefits the patientE) Atropine acts by reactivating the enzyme

29) In tissue bath-1, a ring of normal arterial tissue is suspended. In tissue bath-2 another ring ofarterial tissue after the endothelium is removed is suspended. Acetylcholine was added toboth tissue baths. Arterial tension was reduced significantly with administration ofacetylcholine in tissue bath -1 but not in tissue bath-2. The differential response toacetylcholine in the bath-1 and bath-2 is the action of which of the following substances?

A) BradykininB) EndothelinC) Nitric oxideD) Nitorus oxide


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E) Endothelin derived Contarcting factor

30) A migrant worker presents to the emergency room with respiratory distress. He had beenspraying an organophosphorous insecticide in the fields for several days, and today hebegan to sweat a lot and felt dizzy. By the time he got to the hospital he was drooling,

gasping, and became agitated. These symptoms are due to the inhibition of which of thefollowing enzymes?

A) PseudocholinesteraseB) Adenylyl cyclaseC) PhospholipaseD) AcetylcholinesteraseE) CYP-450

31) A 70 year old man treated for glaucoma with pilocarpine. His vital signs before and aftertreatment are as follows:

Before treatment: BP was 145/92 mmHg and heart rate was 99/minuteAfter treatment: BP is 140/ 85 mmHg and heart rate is 49/minuteWhich among the following actions of pilocarpine is responsible for reduction of heart rate inthis patient?

A) Decrease in cyclic AMPB) Decrease in cyclic GMPC) Decreases in IP3 and DAGD) Increase in IP3 and DAGE) Increase in cGMP

32) A 48 year old farmer is brought to ER because of diarrhea , wheezing, and dyspnea. Onexamination lacrimation, sweating, excess salivation , miosis and fasciculations of voluntarymuscles was evident. Treatment should include which of the following to reactivate theenzyme affected?

A) AtropineB) EpinephrineC) PropronololD) PralidoximeE) Neostigmine

33) After undergoing a minor surgical procedure, A 71 year old man has difficulty in voidingurine.Which of the following is the most appropriate short term pharmacotherapy?

A) AtropineB) BethenocholC) CarbacholD) Neostigmine


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E) Physostigmine

34) A 25 year old lady visits a cosmetologist for her facial wrinkles. Cosmetologist usedbotulinum toxin injection to reduce her facial frown lines. Which of the following mechanism

best describes the action of botulinum injection?

A) Prevents acetylcholine releaseB) Blocks T-type calcium channelsC) Inhibits calcium release from sarcoplasmic reticulum of muscleD) Inhibits uptake of acetylcholine into motor neuronsE) Inhibits reuptake of nor epinephrine into adrenergic neurons

35) With respect to their action on strip of bronchial smooth muscle in an isolated tissue bath,log dose response curves for Drug A and B are plotted in following graph. Drug B whengiven alone does not have any effect on its own. Which is true about Drug A and Drug B

A) Drug A is atropine and B is acetylcholineB) Drug A nor epinephrine and drug B is phenylephrineC) Drug A is epinephrine and B is PhenoxybenzamineD) Drug A is bethanochol and B is atropineE) Drug A is acetylcholine and B is Physostigmine

Drug A +B


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36) 10 year old boy diagnosed to have strabismus, for surgical correction, was anesthetized withhalothane. Succinyl choline was administered to facilitate endotracheal intubation. Twentyminutes later masseter muscle tone remains increased so that his teeth compress theendotracheal tube. Even in other skeletal muscles muscle tone was found to be increased.His body temperature is 39 C (102.2 F), pulse is 125/minute and respiration rate is 20.

Administration of a drug acting by which of the following mechanism is most appropriatenext step to decrease muscle tone?

A) Stimulation of GABA type B receptorsB) Facilitating GABA mediated chloride channel openingC) Inhibiting membrane sodium channelsD) Facilitating Calcium excretion in urineE) Inhibiting calcium release from sarcoplasmic reticulum

48) A 45-year-old man has an elevated blood pressure during a routine health check-up. All threeconsecutive readings are high (average: 150/100 mm Hg). History reveals that the patient is a

chronic smoker and has some breathing difficulty. Which among the following drugs is bestavoided in the management of hypertension in this particular patient?

A) PropranololB) AtenololC) MetoprololD) BetaxololE) Acebutelol

49) Propranolol was given to a patient with mild hypertension. Which among the following adverseeffects can be typically attributed to propranolol in this otherwise healthy patient?

A) PalpitationsB) Fine tremorC) SeizuresD) BradycardiaE) Increased sexual drive

1. A 30 year old epileptic patient was treated with an antiepileptic drug orally. Even after 3weeks there was no improvement. Serum drug concentration was found to be lessthan half the expected concentration. The same drug is then administeredintravenously . In next few days drug achieved the expected plasma concentration andimprovement in his disease (Reduced frequency of seizures). A difference in which ofthe following pharmacokinetic parameters is the most likely explanation for thedifferences in drug concentration in this patient with two different routes?

A. Protein bindingB. Clearance


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C. Volume of distributionD. First pass effectE. Elimination half life

2. A 36-year-old man presents with signs of difficulty in breathing and cough. Preliminary

diagnosis of bronchial asthma was made. Which among the following routes would beconsidered preferable to chronically administer drugs to this patient?

A. IntravenousB. IntramuscularC. OralD. InhalationE. Sublingual

3. A 50 -year-old woman who is a chronic alcoholic complains of dyspepsia, itching andyellowish discoloration of skin. Liver function tests were found abnormal. She was

prescribed a drug to control itching skin. She has a 50% increase in drug clearancebecause of a change in hepatic function. How are these changes expected to affectsteady-state plasma concentration of the drug in her?

A. Increase to 4 times its previous valueB. Increase to 2 times its previous valueC. Remain the sameD. Decrease to one fourth of its previous valueE. Decrease to one half of its previous value

4. An individual rapidly ingests 400 grams of ethanol. Two hour after ingestion, the bloodethanol concentration is 200 mg/L. Four hours after ingestion, the blood concentrationis 150 mg/L. What is the blood concentration 6 hours after ingestion?

A. 25 mg/LB. 37.5 mg/LC. 100 mg/ LD. 50 mg / LE. 75 mg / L

5. To prevent septicemia in a patient brought to ER, immediate antibiotic action wasessential. You decide to administer an antibiotic (acidic in nature ) with a half life of 3hours. In order to attain a desired therapeutic plasma concentration in short time,which of the following measures should be taken?

A. Increase the rate of infusionB. Combine the drug with probenecidC. Administer the appropriate alkalinizing agentD. Administer the appropriate loading dose intravenously before you start

infusion


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E. Administer intravenous bolus injection every 3 hours

6. A 26-year-old woman is worried about her symptoms of motion sickness during her seacruise. She is advised a skin patch of a drug, which would relieve her symptoms of seasickness. Which among the following statements is TRUE about the skin patches?

A. Has more bioavailabiolity than any other routeB. Produces an immediate effectC. Produces effects only for a very short timeD. Ensures uniform and almost constant blood levels of drugE. Has increased risk of adverse drug reactions

7. A 55-year-old man having congestive heart failure is on oral digoxin therapy. He isbeing considered for therapy with verapamil for his cardiac arrhythmias. Realizing thefact that verapamil can increase the risk of digoxin toxicity, verapamil is avoided. Whichamong the following explains the drug interaction between digoxin and verapamil?

A. Verapamil inhibits the function of P-glycoproteinsB. Verapamil induces the drug metabolizing enzymesC. Verapamil inhibits the drug metabolizing enzymesD. Verapamil increases the renal elimination of digoxinE. None of the above

8. Isoniazid, an antituberculosis drug is given in different doses in two individuals whoweigh the same and are of same age. Both belong to different ethnic backgrounds.Which among the following statements best explains the reason for giving an excessdose in one among those patients?

A. Enhanced metabolism of isoniazidB. Decreased metabolism of isoniazidC. Increased volume of distribution of isoniazidD. Decreased volume of distribution of isoniazidE. Delayed excretion of isoniazid

9. A 56-year-old man on cimetidine therapy for peptic ulcer is considered an oralanticoagulant for prevention of deep vein thrombosis. The specific agent considered iswarfarin. Which among the following consequences would you expect if warfarin isprescribed to this patient?

A. Action of warfarin will be decreasedB. Increased risk of bleedingC. Enhanced excretion of cimetidineD. Decreased protein binding of warfarinE. Warfarin will be effective and safe as in any other individual


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10. In phase-1 clinical trails setup, a new antibiotic being tested in an adult person hasfollowing pharmacokinetic parameters:

Clearance= 100 L/hour

Vd= 50Lt1/2= 3 hours .If the drug has to be administered intravenously what dose should be given to quickly obtaina plasma concentration of 10mg/L?

A. 5mgB. 25mgC. 100mgD. 500mgE. 1000mg

11. A 22-year-old lady, who is sexually active and is on oral contraceptives, is diagnosed

with tuberculosis (TB). She is started on standard four drug regimen, which includesrifampin. Which among the following medical advices will you offer to this young lady?

A. Stop rifampin therapyB. Increase the dose of rifampinC. Decrease the dose of rifampinD. Adopt an additional method of contraceptionE. Decrease the dose of oral contraceptives

12. A new drug is being tested against peptic ulcer. To begin with, the drug is being testedin 20 normal volunteers. Which of the following parameters of new drug is tested in thisgroup of volunteers?

A. EffectivenessB. SafetyC. Cost effectivenessD. A very rare side effectE. Both effectiveness and safety

13. After animal studies a new molecule of test drug need to undergo various phases ofclinical trials. Which of the following statement is most appropriate regarding new drugdevelopment?A. Phase -1 conducted in small number of patients to study the efficacy of the drugB. Phase-1 is conducted in large number of patients to study the efficacy of the drugC. Phase -3 is conducted in small number of patients to study the efficacy of the drugD. Phase -2 is conducted to study both the efficacy and safety of the drugE. Phase -4 is monitored by only licensed physicians to report the adverse effects

observed after marketing the drug


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14. Select the transmembrane transport mechanism it best defines the process of lipid-soluble drugs crossing the membrane at a rate proportional to the concentrationgradient across the membrane

A. FiltrationB. Simple diffusionC. Facilitated diffusionD. Active transportE. Endocytosis

15. From the list of acidic compounds mentioned below,which one is best absorbed in thestomach?

A. Ampicillin (pKa = 2.5)B. Aspirin (pKa = 3.0)

C. Warfarin (pKa = 5.0)D. Phenobarbital (pKa = 7.4)E. Phenytoin (pKa = 9.4)

16. A patient with a history of episodic attacks of coughing, wheezing, and shortness ofbreath is being evaluated in the asthma clinic. Several drug treatments with differentroutes of administration are under consideration. Which of the following statementsabout routes of administration is most correct?

A. Blood levels often rise more slowly after intramuscular injection than after oraldosing

B. The "first-pass" effect is the result of metabolism of a drug afteradministration and before it enters the systemic circulation

C. Administration of antiasthmatic drugs by inhaled aerosol is usually associated withmore adverse effects than is administration of these drugs by mouth

D. Bioavailability of most drugs is greater with rectal (suppository) administration thanwith sublingual administration

E. Administration of a drug by transdermal patch is often faster but is associated withmore first-pass metabolism than oral administration

17. A patient with abdominal stab injuries was admitted to hospital. An antibiotic with anelimination half life of 4 hours was continuously infused. What percentage of the steadystate plasma drug concentration will be achieved in 16 hours?


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A. 50%B. 75%C. 87%D. 93%E. 97%

18. A patient having severe sore throat infection has been given 400 mg of Doxycycline(an antibiotic). Plasma concentration of the Doxycycline measured at different timeintervals is as shown in the table below. Wieght of the pateint is 70kg.

To achieve 97% of Css , this drug requires how many hours ?

A. 10 hoursB. 20 hoursC. 25 hoursD. 16hourE. 40 hour

19. Absorption of the drug is most affected by which of the following combination offactors?

A. Plasma protein binding ability and Pka of the drugB. pKa of the drug and pH of mediumC. Volume of distribution and pH of mediumD. Half life and ClearanceE. pH of the drug and pKa of the medium

20. Drug transport across the biological membrane depends upon whether a drug is acidicor basic , pKa and pH of the environment in which it is. Henderson hasselbachequation explains the relation of all these factors. Which of the following statement ismost appropriate with respect to this equation?

A. Acidic drugs are more ionized if pH-pKa is lowB. Basic drugs are more ionized if pH-pKa is high

Time

in

hours

Plasma concentration of Doxycycline

(mg/L of plasma)

0 72

2 55

4 465 36

8 25

10 18


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C. Acidic drugs are more unionized if pH-pKa is highD. Acidic drugs are more unionized if pH-pKa is lowE. Basic drugs are more unionized if pH-pKa is low

21. The pKa of salicylic acid is 3.0. What percentage of the drug is likely to be excreted in

the urine at pH of 5?

A. 0.1%B. 50%C. 1%D. 90%E. 99%

22. A five year old boy has consumed accidentally 30 tablets of phenytoin (an acidic drug ).In this case which of the following statement is true?

A. Acidification of urine facilitates renal excretion of the drugB. Drug is more absorbed in intestine than in stomachC. Drug absorption can be reduced by increasing the stoamch pHD. Drug absorption can be reduced by reducing the stoamch pHE. Drug absorption can be reduced by reducing the intestine pH

23. Most of the drugs after absorption distribute to various body compartments includingplasma, bone, fat tissue and muscle. If the drug is following first order kinetics, whichone of the following statement is true about protein binding and volume of distribution(Vd)

A. A drug must have been restricted to vascular compartment if volume of distributionof this drug is more than 0.12 L/kg body weight

B. In comparison to a 90 % plasma protein bound drug , A 5% plasma proteinbound drug is likely to have more Vd

C. A drug with highest Vd is generally seen in plasma than in tissuesD. A drug known to have restricted its distribution to interstitial body fluids will have an

approximate Vd of 42 L in an adult weighing 70kg.E. Protein binding and Vd of a drug vary with the dose of drug adminstered

24. A 3-year-old child is brought to the emergency department having just ingested a largeoverdose of Amphetamine, a weak base. It is capable of entering most tissues,including the brain. On physical examination, the heart rate is 100/min, blood pressure140/100 mm Hg, and respiratory rate 20/minute.In this case of amphetamine overdose

A. Urinary excretion would be accelerated by administration of NH4ClB. Urinary excretion would be accelerated by giving NaHCO3C. More of the drug would be ionized at blood pH than at stomach pH


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D. Absorption of the drug would be faster from the stomach than from the smallintestine

E. More of the drug is going to be tissue protein bound

25. After proven safety in human volunteers, several hospitals are participating in a studyto test the efficacy of a newly developed drug prior to its release. This drug is designedto lower cholesterol levels. Of the one thousand patients that are involved in this study,half of the participants receive the drug and half receive a placebo. Neither thephysicians in charge of the study nor the patients are permitted to know what thepatients have received. Which of the following steps in the drug development processdoes this scenario most closely describe

A. New Drug Application (NDA)B. Phase I

C. Phase IID. Phase IIIE. Phase IV

26. Alkalanization of urine is justified in case of overdose of

A. Sodium bicarbonateB. MorphineC. AmphetamineD. BarbiturateE. Atropine

27. Traditionally (until recently) to treat infections physcians were prescribing thecombination of penicillin and probenacid .With this kind of combination of drugs whichof the following parameters of penicillin is going to be affected

A. Volume of distributionB. Glomerular filtrationC. BioavailabilityD. BiotransformationE. Duration of action

28. A patient who is taking probenacid is expected to have an increased excretion of whichof the following?

A. WarfarinB. CreatinineC. PenicillinD. TetracyclineE. Uric acid


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29. A continuous IV infusion of a lidocaine is given to a 70 kg patient with cardiacarrythmias. The pharmacokinetic parameters of lidocaine are as follows:Clearance (Cl) : 0.9 L/hour

Vd : 70LT1/2 : 2 hoursHow long will it take for drug levels to reach 93% of steady state ?

A. 5 hoursB. 6 hoursC. 9 hoursD. 8 hoursE. 7 hours

30. Mr. X and Mr. Y who had similar body weight underwent toniselectomy and postoperatively received ciprofloxacin (an antibiotic) . This antibiotic is known to undergo50% clearance through liver and 50% clearance through kidney.

Liver and renal function tests were done in both patients. Test results revealed that:Mr. X has 100 % functioning liver and kidney.Mr. Y is having 100% functioning liver and only 50% functioning kidney.For every 12hour, 600 mg of ciprofloxacin was given to Mr. X. If the drug is metabolized bysame pathways in both patients, which among the following maintenance regimens in Mr.Ywould produce the same average concentration as observed with the Mr. X.

A. 500 mg every 8 hoursB. 500 mg every 12 hoursC. 250 mg every 12 hoursD. 450 mg every 12 hoursE. 125 mg every 6 hours

1) A 54-year-old man is rushed to the emergency department with a blood pressure of 220/180mm Hg and severe palpitation. Careful history from his relatives reveals that he skipped hisantihypertensive pills for the past two days. He was on Propranolol (beta receptorantagonist/blocker) for the past six months. What could be the underlying cause of the latestcomplication in this patient?

A) Upregulation of beta receptorsB) Downregulation of beta receptorsC) Impaired metabolism of epinephrineD) Enhanced renal clearance of propranolol

E) Downregulation of -receptors


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2) A new drug is being tested on animals and the pharmacodynamics and pharmacokinetics arebeing evaluated. Following a series of lab studies in rats, quantal dose-response curves areconstructed. This is:

A) Invalid in the presence of inhibitors of the drug being studied

B) Obtainable only from humansC) Used to determine the statistical variation (standard deviation) of the efficacy of the drugD) Done to determine the therapeutic index of a drugE) Done to determine the maximal efficacy of a drug

3) A 34-year-old man with congestive heart failure is being considered for a diuretic therapy.Drugs X and Y are considered. Drug X maximally increases the urine output by 80% at a doseof 50 mg/Kg. Drug Y maximally increases the urine output by 80% at a dose of 70 mg/Kg.Which of the following conclusions can be made with this available data?

A) Drug X has a smaller volume of distribution than drug Y

B) Drug X is more potent than drug YC) Drug X is less efficacious than drug YD) Drug X is less potent than drug YE) Drug X has a lesser LD50 than drug Y

4) An agonist is known to bind to a G-protein coupled receptor coupled to a Gs protein. Whichamong the following physiological effects would you expect as a consequence of this drug-receptor interaction?

A) Contraction of smooth muscleB) Reduction in the cardiac contractilityC) Increase in the activity of phospholipase CD) Relaxation of the smooth muscleE) Decrease in the activity of adenylyl cyclase

5) The following graph depicts the dose-response relationship of four different agonists namelyW, X, Y and Z. All four drugs act on the same receptor to produce this response. With respectto the following graph, identify the TRUE statement among the following:


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A) Drugs W, X, and Y are equally potentB) Drugs W is the most efficaciousC) Drugs W is most potentD) Drug Z is a partial agonist and is most potentE) Drug Y is the most efficacious

6) A drug with a therapeutic index of 10 would have an:

A) an LD50 of 300 mg/kg and an ED50 of 1 mg/kgB) an ED50 of 600 mg/kg and an LD50 of 20 mg/kgC) an LD50 of 90 mg/kg and a ED50 of 30 mg/kg

D) an LD50 of 300 mg/kg and an ED50 of 30 mg/kgE) an LD50 of 300 mg/kg and a ED50 of 100 mg/kg

7) A 38-year-old woman on oral croticosteroids for over two months develops complains ofpolyuria and polydipsia (increased urine output and increased thirst). Her lab results revealedelevated blood glucose levels. Administration of subcutaneous insulin promptly reduced theglucose levels. What is the kind of antagonism involved in insulin reversing the hyperglycemicaction of steroids?

A) Physiological antagonismB) Competitive antagonismC) Non-competitive antagonismD) Chemical antagonismE) Physical antagonism

8) The graded dose response for norepinephrine (agonist) alone is shown in the graph B. Thecurve that best describes the response of norepinephrine in the presence of a competitiveantagonist is:

A) Curve AB) Curve CC) Curve DD) Curve E


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9) A competitive antagonist:

A) Shifts the dose-response curve down and to the right

B) Partially stimulates the receptor in the absence of an agonistC) Shifts the dose-response curve to the left and upD) Acts at the same site as the agonistE) Shifts the dose-response curve only at low concentrations of the compound

10) The graph with the continuous line shows the log dose response to epinephrine on betareceptors and the graph with the dotted line shows the log dose response to epinephrine withincreasing concentrations of another drug. Which among the following best explains thecharacteristic of the second drug given?

A) Has an intrinsic value of 0B) Irreversibly binds to the adrenergic receptorsC) Has a submaximal intrinsic activityD) It is safer than the agonistE) Has a longer duration of action than the agonist

11) Efficacy of a new analgesic drug is being tested and the results are plotted as a graph.Analyze the following graph and identify the approximate ED50 of the drug tested:

50%

100%%

Respons

e

Log dose


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A) 15 mgB) 35 mgC) 20 mgD) 30 mg

E) 5 mg

12)Minimal increment of drug dosage may or may not be associated with an increasedmagnitude of clinical response. This purely depends upon the nature of the drug. Whichamong the points in the graph below provides you the information in this regard?

A) Point AB) Point BC) Point CD) Point DE) None of the above

ans_pd_pk-ans

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