USMLE/COMLEX STEP 1 PHARMACOLOGY ONE LINERS
EXAM TEST BANK QUESTIONS & CORRECT ANSWERS
(WELL VERIFIED)
Half-life (T1/2) - CORRECT ANSWER >>>Time it takes for amount of drug to fall to half of its
value; this is a constant in first order kinetics (majority of drugs)
Volume of distribution (VD) - CORRECT ANSWER >>>Relates the amount of drug in the body to
the plasma concentration
Cp - CORRECT ANSWER >>>Plasma concentration of a drug at a given time
Clearance (CL) - CORRECT ANSWER >>>The ratio of the rate of elimination of a drug to its
plasma concentration
First pass effect - CORRECT ANSWER >>>The elimination of drug that occurs before it reaches
the systemic circulation
Bioavailability (F) - CORRECT ANSWER >>>The fraction of administered dose of a drug that
reaches systemic circulation
Steady state - CORRECT ANSWER >>>When the rate of drug input equals the rate of drug
elimination
Phase I - CORRECT ANSWER >>>This step of metabolism makes a drug more hydrophilic and
hence augments elimination
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,Oxidation, reduction, hydrolysis - CORRECT ANSWER >>>Different steps of Phase I
Barbiturates, phenytoin, carbamazepine, and rifampin - CORRECT ANSWER >>>Inducers of
Cytochrome P450 (CYP450)
Cimetidine, ketoconazole, erythromycin, isoniazid and grapefruit - CORRECT ANSWER
>>>Inhibitors of CYP450
Glucuronate, acetic acid, and glutathione sulfate - CORRECT ANSWER >>>Products of Phase II
conjugation
First order kinetics - CORRECT ANSWER >>>Type of kinetics when a constant percentage of
substrate is metabolized per unit time
Zero order kinetics - CORRECT ANSWER >>>Drug elimination with a constant amount
metabolized regardless of drug concentration
Loading dose (Cp*(Vd/F)) - CORRECT ANSWER >>>Target plasma concentration times (volume
of distribution divided by bioavailability)
Maintenance dose (Cp*(CL/F)) - CORRECT ANSWER >>>Concentration in the plasma times
(clearance divided by bioavailability)
Affinity - CORRECT ANSWER >>>Strength of interaction between drug and its receptor
Specificity - CORRECT ANSWER >>>Selectivity of a drug for its receptor
Potency - CORRECT ANSWER >>>Amount of drug necessary to elicit a biologic effect; refers to
the drug's strength
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,Efficacy - CORRECT ANSWER >>>Maximum response achieveable from a drug
Full agonist - CORRECT ANSWER >>>Ability of a drug to produce 100% of the maximum
response regardless of the potency
Partial agonist - CORRECT ANSWER >>>Ability to produce less than 100% of the response
Competitive antagonist - CORRECT ANSWER >>>Ability to bind reversibly to the same site as the
drug and without activating the effector system
Noncompetitive antagonist - CORRECT ANSWER >>>Class of drugs with ability to decrease the
maximal response to an agonist
Thyroid and steroid hormones - CORRECT ANSWER >>>A hormone whose mechanism of
action (MOA) utilizes intracellular receptors
Insulin - CORRECT ANSWER >>>A hormone whose MOA utilizes transmembrane receptors
Benzodiazepines and calcium channel blockers - CORRECT ANSWER >>>Class of drugs whose
MOA utilizes ligand gated ion channels
ED50 - CORRECT ANSWER >>>Median effective dose required for an effect in 50% of the
population
TD50 - CORRECT ANSWER >>>Median toxic dose required for a toxic effect in 50% of the
population
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, LD50 - CORRECT ANSWER >>>Dose which is lethal to 50% of the population
Therapeutic index - CORRECT ANSWER >>>Window between therapeutic effect and toxic effect
High therapeutic index - CORRECT ANSWER >>>Term for a high margin of safety
Low therapeutic index - CORRECT ANSWER >>>Term for a narrow margin of safety
Dimercaprol, EDTA - CORRECT ANSWER >>>Antidote used for lead poisoning
Nitrites - CORRECT ANSWER >>>Antidote used for cyanide poisoning
Physostigmine - CORRECT ANSWER >>>Antidote used for anticholinergic poisoning
Atropine, pralidoxime (2-PAM) - CORRECT ANSWER >>>Antidote used for
organophosphate/anticholinesterase poisoning
Deferoxamine - CORRECT ANSWER >>>Antidote used for iron salt toxicity
N-acetylcysteine (Mucomyst) - CORRECT ANSWER >>>Antidote used for acetaminophen (APAP)
toxicity
Dimercaprol - CORRECT ANSWER >>>Antidote for arsenic, mercury, lead, and gold poisoning
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EXAM TEST BANK QUESTIONS & CORRECT ANSWERS
(WELL VERIFIED)
Half-life (T1/2) - CORRECT ANSWER >>>Time it takes for amount of drug to fall to half of its
value; this is a constant in first order kinetics (majority of drugs)
Volume of distribution (VD) - CORRECT ANSWER >>>Relates the amount of drug in the body to
the plasma concentration
Cp - CORRECT ANSWER >>>Plasma concentration of a drug at a given time
Clearance (CL) - CORRECT ANSWER >>>The ratio of the rate of elimination of a drug to its
plasma concentration
First pass effect - CORRECT ANSWER >>>The elimination of drug that occurs before it reaches
the systemic circulation
Bioavailability (F) - CORRECT ANSWER >>>The fraction of administered dose of a drug that
reaches systemic circulation
Steady state - CORRECT ANSWER >>>When the rate of drug input equals the rate of drug
elimination
Phase I - CORRECT ANSWER >>>This step of metabolism makes a drug more hydrophilic and
hence augments elimination
1|Page
,Oxidation, reduction, hydrolysis - CORRECT ANSWER >>>Different steps of Phase I
Barbiturates, phenytoin, carbamazepine, and rifampin - CORRECT ANSWER >>>Inducers of
Cytochrome P450 (CYP450)
Cimetidine, ketoconazole, erythromycin, isoniazid and grapefruit - CORRECT ANSWER
>>>Inhibitors of CYP450
Glucuronate, acetic acid, and glutathione sulfate - CORRECT ANSWER >>>Products of Phase II
conjugation
First order kinetics - CORRECT ANSWER >>>Type of kinetics when a constant percentage of
substrate is metabolized per unit time
Zero order kinetics - CORRECT ANSWER >>>Drug elimination with a constant amount
metabolized regardless of drug concentration
Loading dose (Cp*(Vd/F)) - CORRECT ANSWER >>>Target plasma concentration times (volume
of distribution divided by bioavailability)
Maintenance dose (Cp*(CL/F)) - CORRECT ANSWER >>>Concentration in the plasma times
(clearance divided by bioavailability)
Affinity - CORRECT ANSWER >>>Strength of interaction between drug and its receptor
Specificity - CORRECT ANSWER >>>Selectivity of a drug for its receptor
Potency - CORRECT ANSWER >>>Amount of drug necessary to elicit a biologic effect; refers to
the drug's strength
2|Page
,Efficacy - CORRECT ANSWER >>>Maximum response achieveable from a drug
Full agonist - CORRECT ANSWER >>>Ability of a drug to produce 100% of the maximum
response regardless of the potency
Partial agonist - CORRECT ANSWER >>>Ability to produce less than 100% of the response
Competitive antagonist - CORRECT ANSWER >>>Ability to bind reversibly to the same site as the
drug and without activating the effector system
Noncompetitive antagonist - CORRECT ANSWER >>>Class of drugs with ability to decrease the
maximal response to an agonist
Thyroid and steroid hormones - CORRECT ANSWER >>>A hormone whose mechanism of
action (MOA) utilizes intracellular receptors
Insulin - CORRECT ANSWER >>>A hormone whose MOA utilizes transmembrane receptors
Benzodiazepines and calcium channel blockers - CORRECT ANSWER >>>Class of drugs whose
MOA utilizes ligand gated ion channels
ED50 - CORRECT ANSWER >>>Median effective dose required for an effect in 50% of the
population
TD50 - CORRECT ANSWER >>>Median toxic dose required for a toxic effect in 50% of the
population
3|Page
, LD50 - CORRECT ANSWER >>>Dose which is lethal to 50% of the population
Therapeutic index - CORRECT ANSWER >>>Window between therapeutic effect and toxic effect
High therapeutic index - CORRECT ANSWER >>>Term for a high margin of safety
Low therapeutic index - CORRECT ANSWER >>>Term for a narrow margin of safety
Dimercaprol, EDTA - CORRECT ANSWER >>>Antidote used for lead poisoning
Nitrites - CORRECT ANSWER >>>Antidote used for cyanide poisoning
Physostigmine - CORRECT ANSWER >>>Antidote used for anticholinergic poisoning
Atropine, pralidoxime (2-PAM) - CORRECT ANSWER >>>Antidote used for
organophosphate/anticholinesterase poisoning
Deferoxamine - CORRECT ANSWER >>>Antidote used for iron salt toxicity
N-acetylcysteine (Mucomyst) - CORRECT ANSWER >>>Antidote used for acetaminophen (APAP)
toxicity
Dimercaprol - CORRECT ANSWER >>>Antidote for arsenic, mercury, lead, and gold poisoning
4|Page
