Part 1.2: drugs and the body

Question 1

what happens to a drug from the time it enters the circulating fluid; IV admin causes the drug to directly enter the circulating blood, bypassing the many complications of ___ from other routes

Answer 1

absorption (step 1 in pharmacokinetics)

Question 2

the movement of substances across a cell membrane against the concentration gradient; this process requires the use of energy

Answer 2

active transport

Question 3

synthetic chemicals used to interfere with the functioning of foreign cell populations, causing cell death; this term is frequently used to refer to the drug therapy of neoplasms, but also drug therapy affecting any foreign cell

Answer 3

chemotherapeutic agents

Question 4

the concentration a drug must reach in the tissues that respond to the particular drug to cause the desired therapeutic effect

Answer 4

critical concentration

Question 5

movement of a drug to body tissues; the places where a drug may be distributed depend on the drug’s solubility, perfusion of the area, cardiac output, and binding of the drug to plasma proteins

Answer 5

distribution (step 2 in pharmacokinetics)

Question 6

process by which the presence of a chemical that is biotransformed by a particular enzyme system in the liver causes increased activity of that enzyme system

Answer 6

enzyme induction

Question 7

removal of a drug from the body; primarily occurs in the kidneys, but also skin, lungs, bile or feces

Answer 7

excretion (step 4 of pharmacokinetics)

Question 8

a phenomenon in which drugs given orally are carried directly to the liver after absorption, where they may be largely inactivated by liver enzymes before they can enter the general circulation; oral drugs frequently are given in higher doses than drugs given by other routes because of this early breakdown

Answer 8

first-pass effect

Question 9

the passage of water and water-soluble components from the plasma into the renal tubule

Answer 9

glomerular filtration

Question 10

the time it takes for the amount of drug in the body to decrease to one half of the peak level it previously achieved

Answer 10

half-life

Question 11

liver enzymes tightly packed together in the hepatic intracellular structure, responsible for the biotransformation (metabolism) of chemicals, including drugs

Answer 11

hepatic microsomal system

Question 12

use of a higher dose than what is usually used for treatment to allow the drug to reach the critical concentration sooner

Answer 12

loading dose

Question 13

movement of substances across a semipermeable membrane with the concentration gradient; this process does not require energy

Answer 13

passive diffusion

Question 14

the study of the interactions between the chemical components of living systems and the foreign chemicals, including drugs, that enter living organisms; the way a drug affects a body

Answer 14

pharmacodynamics

Question 15

the study of genetically determined variations in the response to drugs

Answer 15

pharmacogenomics

Question 16

the way the body deals with a drug, including absorption, distribution, biotransformation, and excretion

Answer 16

pharmacokinetics

Question 17

documented effect of the mind on drug therapy; if a person perceives that a drug will be effective, the drug is much more likely to actually be effective

Answer 17

placebo effect

Question 18

specific areas on cell membranes that react with certain chemicals to cause an effect within the cell

Answer 18

receptor sites

Question 19

property of a chemotherapeutic agent that affects only systems found in foreign cells without affecting healthy human cells (e.g., specific antibiotics can affect certain proteins or enzyme systems used by bacteria but not by human cells)

Answer 19

selective toxicity

Question 20

the actual concentration that a drug reaches in the body results from a ____ _______ involving the rate of:
- absorption from site of entry
- distribution to the active site
- metabolism in the liver
- excretion from the body

Answer 20

Dynamic equilibrium

Question 21

Is IM or SC absorbed faster by the body?

Answer 21

IM

Question 22

T/F: if a medication is administered directly into the blood system, the absorption step is skipped

Answer 22

TRUE

Question 23

Slowest route to be absorbed?

Answer 23

Oral

Question 24

Why might an oral medication be coated, or in capsule form?

Answer 24

To prolong the breakdown of compounds by the acidic environment of the stomach

Question 25

Why might food in the stomach change the way that oral medications are absorbed?

Answer 25

when food is present, stomach acidity is higher, and also empties slower, which exposes the medication to the acidic environment for longer and can speed up the breakdown of the medication.
To block this effect, many drugs may be given 1-2 hours before/after meals.

Question 26

T/F: the gender of individuals changes the rate that medications are absorbed by IM injection

Answer 26

True.
Men have more vascular muscles than women do, which means that doses administered to men reach a peak level faster.

Question 27

Factors that affect the absorption of IM medications (3)

Answer 27

• temperature of muscle: cold = vasoconstriction, decreases absorption. hot = vasodilation, increases absorption
• perfusion or blood flow to muscles
• fat content of muscle

Question 28

Factors affecting PO absorption (4)

Answer 28

• acidity of stomach
• length of time in stomach
• blood flow to GI tract
• presence of interacting foods or drugs

Question 29

6. The half-life of a drug

a.is determined by a balance of all pharmacokinetic processes.

b.is a constant factor for all drugs taken by a patient.

c.is only influenced by the fat distribution of the patient.

d.can be calculated with the use of a body surface nomogram.

Answer 29

a) determined by a balance of all pharmacokinetic processes

Question 30

5. Much of the biotransformation that occurs when a drug is taken occurs as part of

a.the protein-binding effect of the drug.

b.the functioning of the renal system.

c.the first-pass effect through the liver.

d.the distribution of the drug to the reactive tissues.

Answer 30

c) the first pass effect through the liver

Question 31

1. Chemotherapeutic agents are drugs that

a.are used only to treat cancers.

b.replace normal body chemicals that are missing because of disease.

c.interfere with foreign cell functioning causing cell death, such as invading microorganisms or neoplasms.

d.stimulate the normal functioning of a cell.

Answer 31

c) interfere with foreign cell functioning causing cell death

Question 32

2. Receptor sites

a.are a normal part of enzyme substrates.

b.are protein areas on cell membranes that react with specific chemicals.

c.can usually be stimulated by many different chemicals.

d.are responsible for all drug effects in the body.

Answer 32

b) are protein areas on cell membranes that react with specific chemicals

Question 33

3. Selective toxicity is

a.the ability of a drug to seek out a specific bacterial species or microorganism.

b.the ability of a drug to cause only specific adverse effects.

c.the ability of a drug to cause fetal damage.

d.the ability of a drug to attack only those systems found in foreign or abnormal cells.

Answer 33

d) ability of a drug to attack only those systems found in foreign or abnormal cells

Question 34

4. When trying to determine why the desired therapeutic effect is not being seen with an oral drug, the nurse should consider

a.the blood flow to muscle beds.

b.food altering the makeup of gastric juices.

c.the weight of the patient.

d.the temperature of the peripheral environment.

Answer 34

b) food altering the makeup of gastric juices

Question 35

7. J.B. has Parkinson disease that has been controlled for several years with levodopa. After he begins a health food regimen with lots of vitamin B6, his tremors return, and he develops a rapid heart rate, hypertension, and anxiety. The nurse investigating the problem discovers that vitamin B6 can speed the conversion of levodopa to dopamine in the periphery, leading to these problems. The nurse would consider this problem

a.a drug–laboratory test interaction.

b.a drug–drug interaction.

c.An accumulation effect.

d.a sensitivity reaction.

Answer 35

b) drug-drug interaction

Question 36

1. Select All That Apply (SATA): When reviewing a drug to be given, the nurse notes that the drug is excreted in the urine. What points should be included in the nurse’s assessment of the patient?

a.The patient’s liver function tests

b.The patient’s bladder tone

c.The patient’s renal function tests

d.The patient’s fluid intake

e.Other drugs being taken that could affect the kidney

f.The patient’s intake and output for the day

Answer 36

c) renal functioning

d) fluid intake

e) other drugs being taken that could affect kidneys

Question 37

2. SATA: When considering the pharmacokinetics of a drug, what points would the nurse need to consider?

a.How the drug will be absorbed

b.The way the drug affects the body

c.Receptor site activation and suppression

d.How the drug will be excreted

e.How the drug will be metabolized

f.The half-life of the drug

Answer 37

a) how drug is Absorbed

d) how drug is Excreted

e) how drug is Metabolized

f) half-life (Distribution)

*remember pharmacokinetics is ADME!

Question 38

3. SATA: Drug–drug interactions are important considerations in clinical practice. When evaluating a patient for potential drug–drug interactions, what would the nurse expect to address?

a.Bizarre drug effects on the body

b.The need to adjust drug dose or timing of administration

c.The need for more drugs to balance the effects of the drugs being given

d.A new therapeutic effect not encountered with either drug alone

e.Increased adverse effects

f.The use of herbal or alternative therapies

Answer 38

b) adjust dose or timing of administration

e) increased adverse effects

f) use of herbal or alt therapies