Description : Drugs acting through receptors exhibit the following features except: A. Structural specificity B. High potency C. Competitive antagonism D. Dependence of action on lipophilicity
Last Answer : D. Dependence of action on lipophilicity
Description : 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 ... lock and key' structural features D. Properties of affinity' and intrinsic activity' are independently variable
Last Answer : D. Properties of ‘affinity’ and ‘intrinsic activity’ are independently variable
Description : To be used as a topically applied ocular beta blocker a drug should have the following properties except: A. Strong local anaesthetic activity B. High lipophilicity C. High ocular capture D. Low systemic activity
Last Answer : A. Strong local anaesthetic activity
Description : 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
Last Answer : D. They have opposite physiological effects
Description : The following is correct about antipsychotic drugs except: A. They only control symptoms of schizophrenia without affecting the basic disorder B. Combination of two or more antipsychotic drugs is ... psychosis high potency drugs are preferred over low potency drugs D. They donot produce dependence
Last Answer : B. Combination of two or more antipsychotic drugs is more efficacious than any single drug
Description : Pyridostigmine differs from neostigmine in that: A. It is more potent orally B. It is longer acting C. It produces less muscarinic side effects D. It does not have any direct action on NM receptors
Last Answer : B. It is longer acting
Description : 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
Last Answer : B. Synergism
Description : 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)
Last Answer : C. Diazepam (pentobarbitone)
Description : Drugs which undergo high degree of first-pass metabolism in liver: A. Have low oral bioavailability B. Are excreted primarily in bile C. Are contraindicated in liver disease D. Exhibit zero order kinetics of elimination
Last Answer : A. Have low oral bioavailability
Description : The antidotal action of sodium nitrite in cyanide poisoning is based on: A. Physical antagonism B. Chemical antagonism C. Physiological antagonism D. Noncompetitive antagonism
Last Answer : B. Chemical antagonism
Description : 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
Last Answer : C. Agonists induce a conformational change in the receptoR
Last Answer : C. Agonists induce a conformational change in the receptor
Description : 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
Last Answer : C. Therapeutic window phenomenon
Description : 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
Last Answer : B. Drugs acting by the same mechanism
Description : The therapeutic index of a drug is a measure of its: A. Safety B. Potency C. Efficacy D. Dose variability
Last Answer : A. Safety
Description : 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 ... consideration in the choice of a drug D. It reflects the capacity of the drug to produce a drastic response
Last Answer : D. It reflects the capacity of the drug to produce a drastic response
Description : Agonistic action on which of the following adrenergic receptors located on ciliary epithelial cells reduces aqueous secretion: A. β1 receptor B. β2 receptor C. α1 receptor D. α2 receptor
Last Answer : D. α2 receptor
Description : Neostigmine is preferred over physostigmine for treating myasthenia gravis because: A. It is better absorbed orally B. It has longer duration of action C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate D. It penetrates blood-brain barrier
Last Answer : C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate
Description : 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
Last Answer : B. It is a rectangular hyperbola
Description : Which of the following terms best describes the antagonism of leukotriene's bronchoconstrictor effect (mediated at leukotriene receptors) by terbutaline (acting a adrenoceptors) in a patient with ... ) Partial agonist (c) Physiologic antagonist (d) Chemical antagonist (e) Noncompetitive antagonist
Last Answer : Ans: C
Description : Hormone receptors possess all the following properties except (A) All of them are proteins (B) They possess a recognition domain (C) They bind hormones with a high degree of specificity (D) Number of receptors in a target cell is constant
Last Answer : Answer : D
Description : 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
Last Answer : C. Noncompetitive antagonist
Description : An addicting drug which produces little or no physical dependence is: A. Diazepam B. Phenobarbitone C. Amphetamine D. Methadone
Last Answer : C. Amphetamine
Description : Which of the following is a type B (unpredictable) adverse drug reaction: A. Side effect B. Toxic effect C. Idiosyncrasy D. Physical dependence
Last Answer : A. Side effect
Description : Adaptive neurophysiological changes produced by repeated administration of a drug, which result in the appearance of characteristic withdrawal syndrome on discontinuation of the drug is called: A. Drug addiction B. Drug abuse C. Psychological dependence D. Physical dependence
Last Answer : D. Physical dependence
Description : The essential feature in drug addiction is: A. Physical dependence B. Psychological dependence C. Both physical and psychological dependence D. Psychiatric abnormality
Last Answer : B. Psychological dependence
Last Answer : C. Idiosyncrasy
Description : Microsomal enzyme induction can be a cause of: A. Tolerance B. Physical dependence C. Psychological dependence D. Idiosyncrasy
Last Answer : A. Tolerance
Description : The cardiac muscarinic receptors: A. Are of the M1 subtype B. Are of the M2 subtype C. Are selectively blocked by pirenzepine D. Function through the PIP2 → IP3/DAG pathway
Last Answer : B. Are of the M2 subtype
Description : 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
Last Answer : C. Orally administered diuretics may not be effective, but the same may work parenterally
Description : Which of the following drugs is administered by intranasal spray/application for systemic action: A. Phenylephrine B. Desmopressin C. Azelastine D. Beclomethasone dipropionate
Last Answer : B. Desmopressin
Description : 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 ... SMON due to halogenated hydroxyquinolines D. Chloramphenicol induced aplastic anaemia is rare among Indians
Last Answer : B. Black races are more responsive to antihypertensive action of beta blockers
Description : An 'orphan drug' is: A. A very cheap drug B. A drug which has no therapeutic use C. A drug needed for treatment or prevention of a rare disease D. A drug which acts on Orphanin receptors
Last Answer : C. A drug needed for treatment or prevention of a rare disease
Description : The mechanism by which neostigmine improves contraction of myasthenic muscle involves: A. Repetitive binding of the acetylcholine molecules to the same receptors at the muscle endplate B. Diffusion of ... Activation of motor end-plate receptors by neostigmine molecules themselves D. All of the above
Last Answer : D. All of the above
Description : Muscarinic cholinergic receptors: A. Are located only on parasympathetically innervated effector cells B. Mediate responses by opening an intrinsic Na+ ion channel C. Are present on vascular endothelium which has no cholinergic nerve supply D. Predominate in the autonomic ganglia
Last Answer : C. Are present on vascular endothelium which has no cholinergic nerve supply
Description : 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
Last Answer : A. Continuous use of agonists
Description : 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
Last Answer : C. Tyrosine protein kinase receptors
Description : 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
Last Answer : C. Both ligand recognition and signal transduction