Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

RUSVM Toxicology > Toxicokinetics II > Flashcards

Toxicokinetics II Flashcards

(55 cards)

Start Studying
1
Q

Chronicity Factor

A

Acute LD50/Chronic LD50

>2 relatively cumulative toxicant

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

Risk Ratio

A

Toxicity:Use Level

Ex: urea toxicity = 300 mg/kg, use level = 100 mg/kg
Risk Ratio: 3:1

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

Henderson Hasselbach Equation

A

PKa of an acid= pH of the medium + log (N/I)
PKa of a base= pH of the medium + log (I/N)

N= nonionized
I= ionized
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The ____________ the pKa of a weak acid, the ___________ the N/I; the _________ the pKa of a weak base, the __________ the N/I.

A

Higher, higher

Lower, higher

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

Absorption of drugs

A

The transfer of the drug from the side of admin to the circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What factors do we take into account for drug absorption?

A 
Molecular size
Lipid solubility
Degree of ionization 
Dissolution of drug in water 
Concentration of drug at absorptive site
Route of administration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The smaller the molecule, the ________ the penetration through pores

A

Faster

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

The greater the lipid solubility, the _____________ the absorption

A

Greater

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

The higher the ratio between N/I, the ______________ the absorption

A

Greater

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

Which is faster: oral absorption of lipid drugs or solid drugs?

A

Lipid drugs

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

What does oral absorption of lipid drugs depend on?

A

Rate of dissolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What two things does the concentration of a drug at an absorptive site depend on?

A

Dose and concentration

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

The higher the conc of a drug, the _________ the absorption

A

Faster

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

List the routes of administration and their absorptive rates in order from fastest to slowest?

A

Sublingual and inhalation- very rapid
IM
SQ
PO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

An increase in blood flow causes an increase or decrease in absorption?

A

Increase

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

What three things can modify blood flow?

A

Drugs
Physiological factors
Dz

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

What two things can decrease blood flow?

A

Shock

Edema

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

What is the main site of absorption for drugs given PO?

A

Duodenum (bc of extensive surface area and rich blood supply)

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

Rate of absorption depends on what?

A

Rate of gastric emptying

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

What 6 factors affect drug absorption from the GI tract?

A 
PO absorption of solid drugs depends on rate of dissolution
Activity of the gut
Presence of other substances
Blood flow
Species
Individual
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Distribution of drugs

A

Transport of drugs from the plasma to the tissues (site of action, site of storage, side of biotransformation)

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

What 3 things affect the distribution of drugs?

A 
Physiochemical properties 
Concentration gradient
Plasma protein binding
Blood Flow
Tissue barriers
Affinity of drugs to certain tissues
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are two physiochemical properties of the drug?

Study These Flashcards
A

Lipid solubility

Degree of ionization

24
Q

What do acidic drugs bind to?
What do basic drugs bind to?
What do steroids bind to?

Study These Flashcards
A

Albumin
Acid alpha-1 glycoproteins and lipoproteins
Globulin

25
Is plasma protein binding reversible or irreversible?
Reversible
26
What is the significance of plasma protein binding?
It prolongs the half-life of the drug
27
In plasma protein binding, the bound form is the _________ form, which means it can't do what 3 things?
Inactive Can't be distributed, metabolized, or excreted by glomerular filtration (PP bound drugs tend to be actively excreted)
28
The rate of binding of the drugs depends mainly on what?
Amount of drug
29
Drugs compete where in plasma protein binding?
On the binding sites
30
True or False. Plasma protein binding depends on the species.
True
31
What is something that can modify plasma protein binding?
Disease
32
List the 4 highly perfused tissues.
Brain Liver Kidney Endocrine glands
33
List the two moderately perfused tissues
Muscle | Skin
34
List the two poorly perfused tissues
Bone | Adipose tissue
35
What 3 things are causes of alterations of blood flow?
Physiological factors Drugs Disease
36
What are the 5 tissue barriers?
``` Brain Eye Testicles Placenta (less effective) Mammary gland ```
37
True or False. If the drug can cross the BBB, then it can cross any barrier in the body.
True
38
Describe the BBB.
``` Tight capillary endothelial junctions Presence of glial cells Flow of CSF into venous drainage Active transport mechanisms High distribution Lipophillic ```
39
What type of transport is used for extrusion of organic acids and bases?
Active transport
40
What factors influence the BBB?
``` Age Inflammation (meningitis) Trauma Allergic rxn Severe hypotension Hypoxia High doses of organic solvents (alcohol) High doses of heavy metals (lead, mercury) ```
41
Tetracycline has an affinity to ______________ in ______________ tissues.
Calcium; skeletal
42
Aminoglycosides have an affinity to __________ tissue.
Kidney
43
Iodine is trapped by what?
Thyroid gland
44
Redistribution of drugs
The movement of the drug from the tissues to the blood
45
How do you measure the distribution of drugs?
By the volume of distribution (Vd)
46
Biotransformation
The chemical alteration of the drug molecule by the cells of the animal
47
What are the two phases of biotransformation?
Phase 1- oxidation, reduction, hydrolysis | Phase 2- conjugation
48
If there is a change in physiochemical properties of a drug, the metabolite is more __________, ___________, and __________.
Water soluble, polar, and ionized
49
If there is a change in pharmacological activity of a drug what occurs?
Bioinactivation or detox of most drugs | Bioactivation or lethal synthesis (few drugs)
50
True or False. Aspirin is an inactive drug. | What is the active metabolite of Aspirin?
False | Salicylic acid
51
True or False. Cortisone is an inactive drug. What is the active metabolite of cortisone?
True. | Hydrocortisone (cortisol)
52
True or False. Parathion is an toxic drug. What is the toxic metabolite of parathion?
False. Nontoxic | Paroxon
53
What are some common sites for biotransformation?
``` Liver- (SER microsomes; hepatocyte cytoplasm, mitochondria, lysosomes, nuclear envelope, plasma membrane) Nervous tissue Kidney GIT Lungs Skin Plasma ```
54
What are the 5 components of hepatic metabolism?
Enzymes lack specificity Enzymatic rxns are saturable rxns Drugs can compete on the same enzyme Enzymes can be induced or inhibited by drugs Microsomal enzymes cause oxidation, reduction, hydrolysis, and conjugation to glucuronic acid
55
What are the two types of metabolic rxns? Which one is synthetic, non synthetic?
Phase 1- oxidation, reduction, hydrolysis (non synthetic) | Phase 2- conjugation (synthetic)

RUSVM Toxicology (23 decks)

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