Pharmacology and Inhalational Agents
(Exam 2) UPDATED ACTUAL Exam
Questions and CORRECT Answers
What is Pharmacokinetics? - CORRECT ANSWER - What the BODY does to the DRUG
Includes absorption, distribution, metabolism, and excretion of drugs
What Determines the Drug Concentration at a Site of Action? - CORRECT ANSWER -
Pharmacokinetics and drug dose
What is Pharmacodynamics? - CORRECT ANSWER - What the DRUG does to the BODY
More specifically, it is the intrinsic sensitivity/responsiveness of the body's receptors to a drug
and the mechanism by which these effects occur
Differs greatly between patients
Involves concepts of potency, efficacy, and therapeutic window
Structure-activity relationships link actions of drugs to their chemical structure
What is Absorption? - CORRECT ANSWER - Process by which a drug moves from site of
administration to the bloodstream
Different routes of administration of drugs (oral, subcutaneous, IV, intramuscular, transdermal,
etc.) will have differing rates of absorption
,What is Distribution? - CORRECT ANSWER - Once a drug is absorbed it is distributed by
the bloodstream throughout the body
Affected by several factors such as:
- The concentration of drug transporters in blood
- Cardiac output
- pH
- Disease conditions (e.g., volume depletion, burns, third spacing)
- Body water composition
- Body fat composition
- Perfusion
How Does Body Water Composition Affect Distribution? - CORRECT ANSWER - Affects
water-soluble drugs such that more water means more distribution of these drugs and vice versa
How Does Body Fat Composition Affect Distribution? - CORRECT ANSWER - Affects fat-
soluble drugs such that increases in body fat increase the distribution of these drugs and vice
versa
How Does Perfusion Affect Distribution? - CORRECT ANSWER - Greatest distribution
occurs in vessel-rich groups (VRG's), which are highly perfused organs such as the heart, lungs,
liver, and brain
VRG's account for 75% of cardiac output, and only 10% of body mass!
What is Biotransformation? - CORRECT ANSWER - The process of altering drug molecules
Usually takes place in the liver but can also take place in adipose tissue, intestine, kidney, lung,
skin
,3 Phases of biotransformation, but we dont care about phase 3
What is Phase 1 of Biotransformation? - CORRECT ANSWER - Yields a polar, water-soluble
metabolite, often still active
Done through oxidation with Cytochrome P450 (most common), reduction, and hydrolysis
What is Phase 2 of Biotransformation? - CORRECT ANSWER - Yields large polar metabolite
by adding hydrophilic groups to make inactive water-soluble compounds for excretion
Done through glucuronidation (most common), conjugation, acetylation, sulfation, and
methylation
What is Cytochrome P450 (CYP)? - CORRECT ANSWER - These are a family of enzymes
found in the body that play a role in metabolizing drugs via oxidation
Found in large quantities in the liver
CYP3A4 accounts for 50% of cytochrome activity
CYP450 enzymes can be inhibited or induced by drugs, resulting in clinically significant drug-
drug interactions that can cause unanticipated adverse reactions or therapeutic failures
What Happens if CYP450 is Inhibited? - CORRECT ANSWER - Drug level GOES UP due to
less metabolism of said drugs by CYP450
Can cause drug toxicity
Examples of things that inhibit CYP450:
, - Acute ethanol (EtOH) use
- Vitamin E
- Grapefruit juice
- The thyroid hormones Ciprofloxacin and Metronidazole
- Omeprazole (decreasing stomach acid, i.e. a treatment for GERD)
- Warfarin (anticoagulant)
What Happens if CYP450 is Induced? - CORRECT ANSWER - Drug level GOES DOWN
due to more metabolism of said drugs by CYP450
Examples of things that induce CYP450 include:
- Chronic EtOH use (more CYP450 enzymes are made in response to excessive long-term
alcohol use thereby increasing drug metabolism)
- Tobacco
- Modafinil
- St John's Wort
- Dexamethasone
- Anti-epileptics
What Happens if a Patient has Cirrhosis? - CORRECT ANSWER - Cirrhosis is liver tissue
damage, thus patients with this condition are less effective at metabolizing drugs due to
decreased levels of CYP450
In other words, cirrhosis is effectively a physical inhibitor of CYP450
How do Genetics Play a Role in Drug Metabolism? - CORRECT ANSWER - Someone may
be born with more or less CYP450 thus affecting drug metabolism
(Exam 2) UPDATED ACTUAL Exam
Questions and CORRECT Answers
What is Pharmacokinetics? - CORRECT ANSWER - What the BODY does to the DRUG
Includes absorption, distribution, metabolism, and excretion of drugs
What Determines the Drug Concentration at a Site of Action? - CORRECT ANSWER -
Pharmacokinetics and drug dose
What is Pharmacodynamics? - CORRECT ANSWER - What the DRUG does to the BODY
More specifically, it is the intrinsic sensitivity/responsiveness of the body's receptors to a drug
and the mechanism by which these effects occur
Differs greatly between patients
Involves concepts of potency, efficacy, and therapeutic window
Structure-activity relationships link actions of drugs to their chemical structure
What is Absorption? - CORRECT ANSWER - Process by which a drug moves from site of
administration to the bloodstream
Different routes of administration of drugs (oral, subcutaneous, IV, intramuscular, transdermal,
etc.) will have differing rates of absorption
,What is Distribution? - CORRECT ANSWER - Once a drug is absorbed it is distributed by
the bloodstream throughout the body
Affected by several factors such as:
- The concentration of drug transporters in blood
- Cardiac output
- pH
- Disease conditions (e.g., volume depletion, burns, third spacing)
- Body water composition
- Body fat composition
- Perfusion
How Does Body Water Composition Affect Distribution? - CORRECT ANSWER - Affects
water-soluble drugs such that more water means more distribution of these drugs and vice versa
How Does Body Fat Composition Affect Distribution? - CORRECT ANSWER - Affects fat-
soluble drugs such that increases in body fat increase the distribution of these drugs and vice
versa
How Does Perfusion Affect Distribution? - CORRECT ANSWER - Greatest distribution
occurs in vessel-rich groups (VRG's), which are highly perfused organs such as the heart, lungs,
liver, and brain
VRG's account for 75% of cardiac output, and only 10% of body mass!
What is Biotransformation? - CORRECT ANSWER - The process of altering drug molecules
Usually takes place in the liver but can also take place in adipose tissue, intestine, kidney, lung,
skin
,3 Phases of biotransformation, but we dont care about phase 3
What is Phase 1 of Biotransformation? - CORRECT ANSWER - Yields a polar, water-soluble
metabolite, often still active
Done through oxidation with Cytochrome P450 (most common), reduction, and hydrolysis
What is Phase 2 of Biotransformation? - CORRECT ANSWER - Yields large polar metabolite
by adding hydrophilic groups to make inactive water-soluble compounds for excretion
Done through glucuronidation (most common), conjugation, acetylation, sulfation, and
methylation
What is Cytochrome P450 (CYP)? - CORRECT ANSWER - These are a family of enzymes
found in the body that play a role in metabolizing drugs via oxidation
Found in large quantities in the liver
CYP3A4 accounts for 50% of cytochrome activity
CYP450 enzymes can be inhibited or induced by drugs, resulting in clinically significant drug-
drug interactions that can cause unanticipated adverse reactions or therapeutic failures
What Happens if CYP450 is Inhibited? - CORRECT ANSWER - Drug level GOES UP due to
less metabolism of said drugs by CYP450
Can cause drug toxicity
Examples of things that inhibit CYP450:
, - Acute ethanol (EtOH) use
- Vitamin E
- Grapefruit juice
- The thyroid hormones Ciprofloxacin and Metronidazole
- Omeprazole (decreasing stomach acid, i.e. a treatment for GERD)
- Warfarin (anticoagulant)
What Happens if CYP450 is Induced? - CORRECT ANSWER - Drug level GOES DOWN
due to more metabolism of said drugs by CYP450
Examples of things that induce CYP450 include:
- Chronic EtOH use (more CYP450 enzymes are made in response to excessive long-term
alcohol use thereby increasing drug metabolism)
- Tobacco
- Modafinil
- St John's Wort
- Dexamethasone
- Anti-epileptics
What Happens if a Patient has Cirrhosis? - CORRECT ANSWER - Cirrhosis is liver tissue
damage, thus patients with this condition are less effective at metabolizing drugs due to
decreased levels of CYP450
In other words, cirrhosis is effectively a physical inhibitor of CYP450
How do Genetics Play a Role in Drug Metabolism? - CORRECT ANSWER - Someone may
be born with more or less CYP450 thus affecting drug metabolism
