Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Pharm SJSM > Block 1 Drug metabolism/elimination/clinical pharmacokinetics > Flashcards

Block 1 Drug metabolism/elimination/clinical pharmacokinetics Flashcards

1
Q

Describe what pharmacodynamics studies

A

Drug concentration & it’s effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe Pharmacokinetics

A

Drug concentration & time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the purpose of phase 1 reactions

A

Aka microsomal metabolism:

Turns lipophilic into a polar/hydrophilic metabolite via c-P450 (liver) via one of the following reactions:
- Oxidation*
- Reduction
- Hydrolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the purpose of phase 2 reactions

A

Involves conjugating a drug into a polar metabolite (inactive) via one of these reactions:
- Glucuronidation*
- Acetylation
- Sulfation
- Methylation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Drug make up:

Describe the properties of lipophilic drugs

A
  1. Usually non-polar they can cross lipid membranes via passive diffusion (BBB, placenta etc)
  2. Mostly excreted via liver
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Drug make up:

Describe the properties of hydrophilic drugs

A
  1. Usually Polar they need facilitated diffusion to pass lipid membranes
  2. Mostly excreted via liver
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Drug make up:

Describe the properties of Amphiphilic drugs

A

have both lipo/hydro-philic properties

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How does Vd change for the elderly?

  • In hydrophilic drugs
A

Hydrophilic drugs = The elderly tend to have less total body water therefor they tend to have lower Vd

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How does Vd change for the elderly?

  • In acidic drugs
A

Acidic drugs = The elderly have less albumin therefor drugs can’t bind or stay in plasma (high Vd)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How does Vd change for the elderly?

  • In lipophilic drugs
A

The elderly tend to have more body fat therefor Higher Vd

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Drug metabolism:

Describe what zero order kinetics are

A
  • When the metabolism/elimination rate stays constant (independent of plasma concentration of the drug at steady state)
  • It’s capacity limited meaning the drug can become over saturated (toxicity)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Types of conjugation:

What are the drugs metabolized via phase II Acetylation?

A

Sulfonamide
Hydralazine
INH
Procainamide & Penicillamine
Dapsone
“SHIPD”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Gastric patients have an increased _____ phase metabolism

A

Phase II metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Drug half-life:

Describe what the:
1. rate of elimination
2. Drug examples

A
  1. The rate of elimination is constant meaning it can become over saturated
  2. “It takes zero PHEN-TAS-E”
    - Phenytoin
    - Aspirin
    - Ethanol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the features of 1st order kinetics

A

The rate of metabolism is directly proportional to the drug’s plasma concentration (meaning it’s dependent on the elimination)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What’s the equation for Vd?

A

Vd =
Q (conc of drug in body)
/
C (conc of drug in plasma)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Intravascular drugs have _____ Vd

A

Low Vd because they are large + charged molecules with a high binding affinity to plasma proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

ECM drugs have a _____ Vd

A

Medium Vd because they are small but hydrophilic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Tissue/fat drugs have a ____ Vd

A

High Vd because they are small + lipophilic & have a higher binding affinity for tissue proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the equation for the half life of a drug (t1/2)

A

t1/2 = (0.7 * Vd) / CL in first order eliminations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How many half lives does it take a drug to reach steady state when infused at a constant rate?

A

4-5 t1/2’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe what steady state is

A

When the rate of a drugs elimination is equal to its rate of administration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What’s the key equation for CL?

A

CL = 0.7 * (Vd / t1/2)

OR

CL = Dosage rate / Plasma concentration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What’s the equation for the loading dose (also what is the loading dose)?

A

Loading dose = CP * Vd / F (bioavail)

Loading dose is the amount of drug needed to cause an initial therapeutic effect (typically administered in ER situations to stabilize

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
In renal & liver disease (hypoalbuminemia) how are loading & maintenance doses effected?
Loading dose is unaffected & Maintenace dose decreases
26
What is the equation for Maintenace dose?
Maintenance dose = CP * CL * t (dosage int) / F
27
Lipophilic drugs are metabolized via one of two phases: Phase 1 is primarily CYP450 dependent & involves which reactions and produces what kind of metabolites?
Reactions: Hydroxylation Oxidation Reduction Metabolites: slightly polar
28
Lipophilic drugs are metabolized via one of two phases: Phase 2 involves which reactions and produces what kind of metabolites?
Reactions: Methylation Acetylation Glucuronidation Sulfation Metabolites: Very polar (except acetylation)
29
In phase 2 metabolism, all reactions products are very polar except for acetylation. Which drugs are metabolized in this phase via acetylation?
Sulfonamides Hydralazine INH Procainamide Dapsone "SHIPD"
30
Efficacy describes the what?
The max effect a drug can cause (aka the Vmax)
31
Potency describes the what?
The amount of drug that is needed to cause an effect (EC50)
32
What type of receptor binding is this, describe it
Competitive antagonist: Decreased potency unchanged efficacy Can be overcome with lots of agonists
33
Diazepam + Flumazenil on GABA receptors = decreased potency describes flumazenil as what type of binding receptor?
competitive antagonist
34
What type of receptor binding is this, describe it
Decreased Efficacy Unchanged potency It can't be overcome by more agonists
35
Norepi + phenoxybenzamine on alpha receptors = decreased efficacy describes phenoxybenzamine as what type of binding receptor?
Non-competitive antagonist
36
What type of receptor binding is this, describe it
Decreased efficacy Unchanged potency It acts on the same site as the full agonist
37
Morphine + buprenorphine at mew opiod receptors = decreased efficacy & independent potency depending on the drugs
Partial agonist
37
Effects of drugs: When the effect of A & B together is equal to their individual effects
Additive effect
37
Aspirin + acetaminophen administered together is an example of what type of drug effect?
Additive effect
37
Effects of drugs: When drug A is needed to get the full effect of Drug B
Permissive effect
37
Drug effect: When the effect of drug A & drug B together is greater than their individual effects
Synergistic effect
37
Clopidogrel increases the effect of aspirin administered together, describes what kind of drug effect?
Synergistic effect
38
When the effects of drugs A & B together are grater but drug B doesn't actually have a therapeutic effect, this describes what type of drug effect?
Potentiation effect
39
Carbidopa only blocks the enzyme that metabolizes levodopa but this increases levodopa's effect, this describes what type of drug effect?
potentiation effect
40
When the effect of drugs A & B together is LESS than their individual effects, describes which type of drug effect?
Antagonistic effect
41
Ethanol is used as an antidote to decrease the effect of methanol toxicity, describes what type of drug effect?
Antagonistic effect
42
Repeated use of a drug causes it to have less of an effect (sensitization), describes what kind of drug effect?
Tachyphylactic effect
43
Describe what redistribution means for drugs
this describes the fast acting & terminating effects of very lipid soluble drugs on the BBB & Heart
44
Thiopentone sodium & Propofol are examples of drugs that undergo ________
Redistribution
45
Describe zero order kinetics
drug elimination is capacity limited meaning it can become over saturated (the graph won't be linear)
46
Zero order drugs include (4)
Phenytoin Ethyl alcohol Theophylline Aspirin
47
List the CYP450 Inducers
St. Johns wort Phenytoin Phenobarbitone Modafinil Nevirapine Rifampin Griseofulvin Carbamazepine Chronic alcohol
48
St. Johns wort Phenytoin Phenobarbitone Modafinil Nevirapine Rifampin Griseofulvin Carbamazepine Chronic alcohol Are all examples of CYP450
Inducers
49
St. Johns wort Phenytoin Phenobarbitone are examples of
CYP450 Inducers
50
Modafinil Nevirapine Rifampin Are examples of
CYP450 Inducers
51
Griseofulvin Carbamazepine Chronic alcohol Are examples of
Cyp450 Inducers
52
List the CYP450 Inhibitors
Sodium Valproate Isoniazid (INH) Cimetidine Ketoconazole Fluconazole Acute Alcohol Chloramphenicol Erythromycin Sulfonamides Ciprofloxacin Omeprazole Amiodarone Ritonavir Grapefruit juice
53
Sodium Valproate Isoniazid (INH) Cimetidine Ketoconazole Fluconazole Acute Alcohol Chloramphenicol Erythromycin Sulfonamides Ciprofloxacin Omeprazole Amiodarone Ritonavir Grapefruit juice Are all examples of
CYP450 Inhibitors | SICK FACES COme when I AM Really drinking GF juice
54
Sodium Valproate Isoniazid (INH) Cimetidine Are examples of
CYP450 Inhibitors
55
Ketoconazole Fluconazole Acute Alcohol Are examples of
CYP450 Inhibitors
56
Chloramphenicol Erythromycin Sulfonamides Are examples of
CYP450 Inhibitors
57
Ciprofloxacin Omeprazole Amiodarone Are examples of
CYP450 Inhibitors
58
Ritonavir Grapefruit juice Are examples of
CYP450 Inhibitors
59
List the substrates of CYP450
Theophylline OCP's Anti-Epileptics Warfarin
60
Theophylline OCP's Anti-Epileptics Warfarin Describes what
CYP450
61
Theophylline OCP's Describes what
CYP450 substrate
62
Anti-Epileptics Warfarin Describes what
CYP450 Substrates
63
Describe the actions of an agonist
they bind & mimics a substance in our body (i.e morphine) Affinity & Efficacy = 1
64
Describe an antagonist
a drug that blocks receptors of a substance preventing its effect. i.e Naxolone
65
Describe an inverse agonist
When a drug binds a receptor but produces the opposite effect that the endogenous substance was supposed to (vasocontraction instead of vasodilation)
66
flumazenil binds to the same receptors as benzodiazepines (drugs that reduce anxiety) but instead of calming the brain, it produces an opposite effect and increases anxiety levels This describes a ______
Inverse agonist
67
Describe a partial agonist
When a drug is only partly as effective as a full agonist. But it acts as a competitive antagonist when there is a full agonist around Affinity = 1 Efficacy < 1
68
buprenorphine, which is used to treat opioid addiction. It has both agonist and antagonist properties and binds to opioid receptors in the brain, producing some opioid-like effects but not as strongly as full agonists like heroin This describes ______
Partial agonist that can act as a competitive inhibitor to heroin
69

Pharm SJSM (23 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions