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 : Th effect or response produced by two or more chemicals are less than the sum of the effects or response that the chemical would produce individually is known as - (1) Antagonism (2) Independent (3) Additive (4) Synergism
Last Answer : (1) Antagonism Explanation: Synergy is the interaction of multiple elements in a system to produce an effect different from or greater than the sum of their individual effects. On the other hand, ... of two or more substances to produce an effect less than the sum of their individual effects.
Description : The effect or response produced by two or more chemicals are less than the sum of the effects or response that the chemical would produce individually is known as (1) Antagonism (2) Independent (3) Additive (4) Synergism
Last Answer : Antagonism
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 : 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 : Eposure to mixtures of chemicals are greater than expected on the basis of effects of expo-sure to each chemical individually. This is known as – (1) Additives (2) Antagonism (3) Synergism (4) Independent
Last Answer : (3) Synergism Explanation: When the toxic effect of the mixture is greater than that expected for the sum of individual constituent doses, which is that effects of combined doses are more- ... less than that expected under the dose additivity assumption, the interactions are said to be antagonistic.
Description : Exposure to mixtures of chemicals are greater than expected on the basis of effects of exposure to each chemical individually. This is known as (1) Additives (2) Antagonism (3) Synergism (4) Independent
Last Answer : Synergism
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 : 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 mechanisms involved in the causation of dangerous cardiac arrhythmias due to overdose of tricyclic antidepressants include the following except: A. Intraventricular conduction block B. Potentiation of noradrenaline C. Antagonism of acetylcholine D. Increased vagal tone
Last Answer : D. Increased vagal tone
Description : Weakly acidic drugs: A. Are bound primarily to α1 acid glycoprotein in plasma B. Are excreted faster in alkaline urine C. Are highly ionized in the gastric juice D. Do not cross blood-brain barrier
Last Answer : B. Are excreted faster in alkaline urine
Description : Majority of drugs cross biological membranes primarily by: A. Passive diffusion B. Facilitated diffusion C. Active transport D. Pinocytosis
Last Answer : A. Passive diffusion
Last Answer : C. Is affected by extent of ionization of drug molecules
Description : Monitoring of blood levels of diuretic drugs is not practised because: A. No sensitive methods for measuring blood levels of diuretics are available B. It is easier to measure the effect of these ... Response to diuretics is not related to their blood levels D. Diuretics need activation in the body
Last Answer : B. It is easier to measure the effect of these drugs
Description : The following statement is true in relation to drug toxicity' and poisoning': A. The two terms are synonymous B. When a toxic effect requires specific treatment, it is called poisoning C. ... is called poisoning D. Toxicity is caused by drugs while poisoning is caused by other harmful chemicals
Last Answer : C. A toxic effect which endangers life by markedly affecting vital functions is called poisoning
Description : Significant tolerance does not develop to the following action of morphine: A. Analgesia B. Euphoria C. Sedation D. Miosis
Last Answer : D. Miosis
Description : 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
Last Answer : A. Antisecretory action of atropine
Description : Microsomal enzyme induction can be a cause of: A. Tolerance B. Physical dependence C. Psychological dependence D. Idiosyncrasy
Last Answer : A. Tolerance
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 : 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
Last Answer : C. Tubular transport mechanisms are not well developed
Description : The most commonly occurring conjugation reaction for drugs and their metabolites is: A. Glucuronidation B. Acetylation C. Methylation D. Glutathione conjugation
Last Answer : A. Glucuronidation
Description : The anticholinesterase action of edrophonium is short lasting because termination of its action depends on: A. Dissociation and diffusion of the drug from the enzyme B. Hydrolysis of the drug by the enzyme C. Synthesis of fresh enzyme molecules D. A combination of the above three processes
Last Answer : A. Dissociation and diffusion of the drug from the enzyme
Description : 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
Last Answer : C. Corticosteroid
Description : 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 ... adjusted D. The time course of action of the different components may not be identical
Last Answer : B. Contraindication to one of the components does not contraindicate the formulation
Description : The most vulnerable period of pregnancy for the causation of foetal malformations due to drugs is: A. 18-55 days of gestation B. 56-84 days of gestation C. Second trimester D. 36 weeks onwards
Last Answer : A. 18-55 days of gestation
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 : 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
Last Answer : A. Attainment of steady-state plasma concentration of drugs eliminated through the kidney is hastened
Description : 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
Last Answer : D. Disposition of atenolol is not significantly affected
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 : 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 : 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
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 : A prodrug is: A. The prototype member of a class of drugs B. The oldest member of a class of drugs C. An inactive drug that is transformed in the body to an active metabolite D. A drug that is stored in body tissues and is then gradually released in the circulation
Last Answer : C. An inactive drug that is transformed in the body to an active metabolite
Description : Biotransformation of drugs is primarily directed to: A. Activate the drug B. Inactivate the drug C. Convert lipid soluble drugs into nonlipid soluble metabolites D. Convert nonlipid soluble drugs into lipid soluble metabolites
Last Answer : C. Convert lipid soluble drugs into nonlipid soluble metabolites
Description : Marked redistribution is a feature of: A. Highly lipid soluble drugs B. Poorly lipid soluble drugs C. Depot preparations D. Highly plasma protein bound drugs
Last Answer : A. Highly lipid soluble drugs
Description : Which of the following is not true of the blood-brain barrier: A. It is constituted by tight junctions between the endothelial cells of brain capillaries and the glial tissue B. It allows passage ... of highly ionized drugs into the brain D. It regulates passage of substances from brain into blood
Last Answer : D. It regulates passage of substances from brain into blood
Description : The blood-brain barrier, which restricts entry of many drugs into brain, is constituted by: A. P-glycoprotein efflux carriers in brain capillary cells B. Tight junctions between endothelial cells of brain capillaries C. Enzymes present in brain capillary walls D. All of the above
Last Answer : D. All of the above
Description : Tricyclic antidepressants can alter the oral absorption of many drugs by: A. Complexing with the other drug in the intestinal lumen B. Altering gut motility C. Altering gut flora D. Damaging gut mucosa
Last Answer : B. Altering gut motility
Description : The most important factor which governs diffusion of drugs across capillaries other than those in the brain is: A. Blood flow through the capillary B. Lipid solubility of the drug C. pKa value of the drug D. pH of the medium
Last Answer : A. Blood flow through the capillary
Description : Which of the following drugs is most likely to be absorbed from the stomach: A. Morphine sulfate B. Diclofenac sodium C. Hyoscine hydrobromide D. Quinine dihydrochloride
Last Answer : B. Diclofenac sodium
Description : 3 Diffusion of drugs across cell membrane: A. Is dependent upon metabolic activity of the cell B. Is competitively inhibited by chemically related drugs C. Is affected by extent of ionization of drug molecules D. Exhibits saturation kinetics
Description : Alkalinization of urine hastens the excretion of: A. Weakly basic drugs B. Weakly acidic drugs C. Strong electrolytes D. Nonpolar drugs
Last Answer : A. Weakly basic drugs