3.1 Which of the following drugs acts by inhibiting an enzyme in the body:
A. Atropine
B. Allopurinol
C. Levodopa
D. Metoclopramide
3.2 The following is a competitive type of enzyme inhibitor:
A. Acetazolamide
B. Disulfiram
C. Physostigmine
D. Theophylline
3.3 What is true in relation to drug receptors:
A. All drugs act through specific receptors
B. All drug receptors are located on the surface of the target cells
C. Agonists induce a conformational change in the receptor
D. Partial agonists have low affinity for the receptor
3.4 Drugs acting through receptors exhibit the following features except:
A. Structural specificity
B. High potency
C. Competitive antagonism
D. Dependence of action on lipophilicity
3.5 Study of drug-receptor interaction has now shown that:
A. Maximal response occurs only when all receptors are occupied by the drug
B. Drugs exert an ‘all or none’ action on a receptor
C. Receptor and drugs acting on it have rigid
complementary ‘lock and key’ structural features
D. Properties of ‘affinity’ and ‘intrinsic activity’ are independently variable
3.6 A partial agonist can antagonise the effects of a full agonist because it has:
A. High affinity but low intrinsic activity
B. Low affinity but high intrinsic activity
C. No affinity and low intrinsic activity
D. High affinity but no intrinsic activity
3.7 Receptor agonists possess:
A. Affinity but no intrinsic activity
B. Intrinsic activity but no affinity
C. Affinity and intrinsic activity with a + sign
D. Affinity and intrinsic activity with a – sign
3.8 Agonists affect the receptor molecule in the following manner:
A. Alter its amino acid sequence
B. Denature the receptor protein
C. Alter its folding or alignment of subunits
D. Induce covalent bond formation
3.9 Receptors perform the following function/functions:
A. Ligand recognition
B. Signal transduction
C. Both ligand recognition and signal transduction
D. Disposal of agonists and antagonists
3.10 The following receptor type has 7 helical membrane spanning amino acid segments with 3 extracellular
and 3 intracellular loops:
A. Tyrosine protein kinase receptor
B. Gene expression regulating receptor
C. Intrinsic ion channel containing receptor
D. G protein coupled receptor
3.11 Which of the following is a G protein coupled receptor:
A. Muscarinic cholinergic receptor
B. Nicotinic cholinergic receptor
C. Glucocorticoid receptor
D. Insulin receptor
3.12 The following receptor has an intrinsic ion channel:
A. Histamine H1 receptor
B. Histamine H2 receptor
C. Adrenergic alfa receptor
D. GABA-benzodiazepine receptor
3.13 Select the receptor that is located intracellularly:
A. Opioid μ receptor
B. Steroid receptor
C. Prostaglandin receptor
D. Angiotensin receptor
3.14 Agonist induced autophosphorylation, internalization
and down regulation is a distinctive feature of:
A. G-protein coupled receptors
B. Intrinsic ion channel containing receptors
C. Tyrosine protein kinase receptors
D. Receptors regulating gene expression
3.15 All of the following subserve as intracellular second messengers in receptor mediated signal transduction except:
A. Cyclic AMP
B. Inositol trisphosphate
C. Diacyl glycerols
D. G proteins
3.16 The receptor transduction mechanism with the fastest time-course of response effectuation is:
A. Adenylyl cyclase-cyclic AMP pathway
B. Phospholipase C-IP3: DAG pathway
C. Intrinsic ion channel operation
D. Protein synthesis modulation
3.17 A receptor which itself has enzymatic property is:
A. Insulin receptor
B. Progesterone receptor
C. Thyroxine receptor
D. Glucagon receptor
3.18 Down regulation of receptors can occur as a consequence of:
A. Continuous use of agonists
B. Continuous use of antagonists
C. Chronic use of CNS depressants
D. Denervation
3.19 The following statement is not true of log dose-response curve:
A. It is almost linear except at the ends
B. It is a rectangular hyperbola
C. It facilitates comparison of different agonists
D. It can help in discriminating between competitive and noncompetitive antagonists
3.20 When therapeutic effects decline both below and above a narrow range of doses, a drug is said to exhibit:
A. Ceiling effect
B. Desensitization
C. Therapeutic window phenomenon
D. Nonreceptor mediated action
3.21 Which of the following drugs exhibits ‘therapeutic window’ phenomenon:
A. Captopril
B. Furosemide
C. Diazepam
D. Imipramine
3.22 The following statement is not true of ‘potency’ of a drug:
A. Refers to the dose of the drug needed to produce
a certain degree of response
B. Can be related to that of its congeners by the
relative position of its dose-response curve on the dose axis
C. It is often not a major consideration in the choice of a drug
D. It reflects the capacity of the drug to produce a drastic response
3.23 ‘Drug efficacy’ refers to:
A. The range of diseases in which the drug is beneficial
B. The maximal intensity of response that can be produced by the drug
C. The dose of the drug needed to produce half maximal effect
D. The dose of the drug needed to produce therapeutic effect
3.24 Which of the following is always true:
A. A more potent drug is more efficacious
B. A more potent drug is safer
C. A more potent drug is clinically superior
D. A more potent drug can produce the same response at lower doses
3.25 Higher efficacy of a drug necessarily confers:
A. Greater safety
B. Therapeutic superiority
C. Capacity to produce more intense response
D. Cost saving
3.26 If the dose-response curves of a drug for producing different actions are widely separated on the dose
axis, the drug is:
A. Highly potent
B. Highly efficacious
C. Highly toxic
D. Highly selective
3.27 The therapeutic index of a drug is a measure of its:
A. Safety
B. Potency
C. Efficacy
D. Dose variability
3.28 Compared to the drug named within parenthesis, which of the following drugs has a higher potency but lower efficacy:
A. Pethidine (morphine)
B. Furosemide (hydrochlorothiazide)
C. Diazepam (pentobarbitone)
D. Enalapril (captopril)
3.29 If the effect of combination of two drugs is equal to the sum of their individual effects, the two drugs are
exhibiting:
A. Potentiation
B. Synergism
C. Cross tolerance
D. Antagonism
3.30 The antagonism between adrenaline and histamine is called ‘physiological antagonism’ because:
A. Both are physiologically present in the body
B. They act on physiological receptors
C. Both affect many physiological processes
D. They have opposite physiological effects
3.31 The antidotal action of sodium nitrite in cyanide poisoning is based on:
A. Physical antagonism
B. Chemical antagonism
C. Physiological antagonism
D. Noncompetitive antagonism
3.32 A drug ‘R’ producing no response by itself causes the log dose-response curve of another drug ‘S’ to shift to the right in a parallel manner without decreasing the
maximal response: Drug ‘R’ is a:
A. Partial agonist
B. Inverse agonist
C. Competitive antagonist
D. Noncompetitive antagonist
3.33 A drug which does not produce any action by itself but decreases the slope of the log dose-response curve and suppresses the maximal response to another drug is a:
A. Physiological antagonist
B. Competitive antagonist
C. Noncompetitive antagonist
D. Partial agonist
3.34 The following is not a feature of competitive antagonists:
A. Chemical resemblance with the agonist
B. Parallel rightward shift of the agonist log dose- response curve
C. Suppression of maximal agonist response
D. Apparent reduction in agonist affinity for the receptor
3.35 The following is a competitive antagonist of GABA but a noncompetitive antagonist of diazepam:
A. Picrotoxin
B. Muscimol
C. Flumazenil
D. Bicuculline
3.36 The dose of the following class of drugs has to be adjusted by repeated measurement of the affected physiological parameter:
A. Oral contraceptives
B. Antiepileptics
C. Antidepressants
D. Oral anticoagulants
3.37 A drug which is generally administered in standard doses without the need for dose individualization is:
A. Insulin
B. Mebendazole
C. Prednisolone
D. Digoxin
3.38 Which of the following statements is not true of fixed
dose combination formulations:
A. They are more convenient
B. Contraindication to one of the components does not contraindicate the formulation
C. The dose of any one component cannot be independently adjusted
D. The time course of action of the different components may not be identical
3.39 Fixed dose combination formulations are not necessarily
appropriate for:
A. Drugs administered in standard doses
B. Drugs acting by the same mechanism
C. Antitubercular drugs
D. Antihypertensive drugs
3.40 A fixed dose combination preparation meant for internal use must not contain the following class of drug:
A. Thiazide diuretic
B. Fluoroquinolone antimicrobial
C. Corticosteroid
D. H2 blocker
3.41 Interindividual variations in equieffective doses of a drug are most marked if it is disposed by:
A. Glomerular filtration
B. Tubular secretion
C. Both glomerular filtration and tubular secretion
D. Hepatic metabolism
3.42 The pharmacokinetics of drugs in the neonate differs from that in adults, because their:
A. Intestinal transit is fast
B. Drug metabolizing enzymes are overactive
C. Tubular transport mechanisms are not well developed
D. Glomerular filtration rate is high
3.43 Which adverse drug effect is more common in children than in adults:
A. Isoniazid induced neuropathy
B. Chlorpromazine induced muscle dystonia
C. Digoxin induced cardiac arrhythmia
D. Penicillin hypersensitivity
3.44 The elderly patients are relatively intolerant to:
A. Digoxin
B. Salbutamol
C. Propranolol
D. Nifedipine
3.45 The following drug adverse effect is specially noted in men compared to women:
A. Tardive dyskinesia due to neuroleptics
B. Levodopa induced abnormal movements
C. Ampicillin induced loose motions
D. Ketoconazole induced loss of libido
3.46 Which racial difference in response to drugs has been
mentioned incorrectly below:
A. Africans require higher concentration of atropine to dilate pupils
B. Black races are more responsive to antihyper-
tensive action of beta blockers
C. Japanese are more prone to develop SMON due
to halogenated hydroxyquinolines
D. Chloramphenicol induced aplastic anaemia is rare among Indians
3.47 Which of the following adverse drug reactions is due to a specific genetic abnormality:
A. Tetracycline induced sunburn like skin lesions
B. Quinidine induced thrombocytopenia
C. Metoclopramide induced muscle dystonia
D. Primaquine induced massive haemolysis
3.48 Drug metabolism can be induced by the following factors except:
A. Cigarette smoking
B. Acute alcohol ingestion
C. Exposure to insecticides
D. Consumption charcoal broiled meat
3.49 A drug which produces qualitatively different actions when administered through different routes is:
A. Phenytoin sodium
B. Hydralazine
C. Magnesium sulfate
D. Nitroglycerine
3.50 Which of the following is true of ‘placebos’:
A. Placebo is a dummy medication
B. Placebo is the inert material added to the drug for making tablets
C. Placebos do not produce any effect
D. All patients respond to placebos
3.51 In patients of hepatic cirrhosis:
A. The extent of change in pharmacokinetics of drugs can be predicted from the values of liver function tests
B. High doses of furosemide can be safely used
C. Metformin is the preferred oral hypoglycaemic
D. Disposition of atenolol is not significantly affected
3.52 In patients with renal insufficiency the clearance of the
following drug is reduced parallel to the reduction in creatinine clearance:
A. Propranolol
B. Digoxin
C. Lignocaine
D. Verapamil
3.53 The following statement is not correct for uremic patients:
A. Attainment of steady-state plasma concentration of drugs eliminated through the kidney is hastened
B. Pethidine can cause seizures
C. Diazepam produces exaggerated CNS depression
D. Tetracyclines further raise blood urea level
3.54 In congestive heart failure patients:
A. Volume of distribution of all drugs is increased
B. Hepatic clearance of drugs is unaffected
C. Orally administered diuretics may not be effective, but the same may work parenterally
D. Inotropic action of digoxin is attenuated
3.55 Interaction between the following pair of drugs can be avoided by making suitable adjustments:
A. Levodopa and metoclopramide
B. Furosemide and indomethacin
C. Tetracyclines and ferrous sulfate
D. Clonidine and chlorpromazine
3.56 Drug cumulation is the basis of organ toxicity of the following drug when used for prolonged periods:
A. Prednisolone
B. Chloroquine
C. Aspirin
D. Hydralazine
3.57 Tolerance is generally not acquired to:
A. Antisecretory action of atropine
B. Sedative action of chlorpromazine
C. Emetic action of levodopa
D. Vasodilator action of nitrates
3.58 Significant tolerance does not develop to the following action of morphine:
A. Analgesia
B. Euphoria
C. Sedation
D. Miosis
3.59 In an anaesthetized dog, repeated intravenous injection of ephedrine shows the phenomenon of:
A. Anaphylaxis
B. Tachyphylaxis
C. Idiosyncrasy
D. Drug resistance
3.1 B 3.2 C 3.3 C 3.4 D 3.5 D 3.6 A 3.7 C 3.8 C 3.9 C 3.10 D 3.11 A 3.12 D 3.13 B 3.14 C 3.15 D 3.16 D 3.16 C 3.17 C 3.17 A 3.18 A 3.19 B 3.20 C 3.21 C 3.21 D 3.22 D 3.23 D 3.23 B 3.24 D 3.25 D 3.25 C 3.26 D 3.27 A 3.28 C 3.29 B 3.30 B 3.30 D 3.31 B 3.32 B 3.32 C 3.33 C 3.33 C 3.34 C 3.34 C 3.35 C 3.35 D 3.36 D 3.37 D 3.37 B 3.38 B 3.38 B 3.39 B 3.39 B 3.40 B 3.40 C 3.41 D 3.42 D 3.42 C 3.43 C 3.43 B 3.44 B 3.44 A 3.45 A 3.45 D 3.46 B 3.47 B 3.47 D 3.48 D 3.48 B 3.49 B 3.49 C 3.50 C 3.50 A
3.51 D 3.52 B 3.53 A 3.54 C 3.55 C 3.56 C 3.56 B 3.57 B 3.57 A 3.58 A 3.58 D 3.59 D 3.59 B