Pharmacokinetics A and D Flashcards

1
Q

Quantitative description of the time course of drug distribution in the body

A

Absorption
o Distribution
o Biotransformation [metabolism]
o Excretion

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

Ethyl alcohol absorption

A

Small intenstine most 75-80%
stomach 20-25%
colon negibile

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

How is ethyl alcohol absorbed

A

through mucosal surfaces of the GI tract
-simple difussion

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

Ficks Law

A

Rate is proportional to the concentration gradient of alcohol across a membrane and to a diffusion coefficient that is constant for ethyl alcohol and specific membrane

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

Factors Affecting absorption

A

Food, concentration and dose, physiology and drugs

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

How does food affect absoprtio

A

reduced efficiency of absorption due to prolonged gastric emptying time
Reduces and shifts the right
Isn’t released into small intestine since small intestine is closed to absorbed food

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Time to peak Alcohol concetration

A

Fasting .5-2 hours
nonfasting 1-3 hrs

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

What has impact with food on alcohol

A

Directly proportional to size of meal
Indirectly proportion to elapsed time from food intake and alcohol consumption
reduction in Cpmax 9-23%

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

Time to peak alcohol concetration

A

Peak generally occurring in less than 30 minutes
Winek et al

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

Variation in BAC after last drink

A

Gullberg and Predmore
Mean time to reach peak BAC, with and without food was 19 minutes
Breen et al (1998)
Avg time to peak after one for the road: 16 – 20 minutes

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

Concentration and dose

A

Alcohol is most rapidly absorbed when the concentration is between 10 – 30%

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

Concentration dilute solutions

A

Result in a lower concertation gradient across the absorbing membrane
Larger volume may delay gastric emptying

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

concentration solution grater

A

irritating to the gastric mucosa and pyloric sphincter
Causing increased secretion of mucosa and delayed gastric emptying
Tripling the dose from 0.4 to 1.2 g/kg of alcohol, produces a 79% increase in time required to achieve peak BAC in fasting subjects and a 61% increase in non-fasting subjects

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

Physiology and drug

A

Changes in motility, blood supply, or morphology of the GI tract
Whether induced by internal or external factors, may result in a significant change in the rate of absorption of ethyl alcohol

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

Physiologoy increasing abosrption

A

Increased GI motility
Chronic gastritis or ulcers
Cholinergic
Increase GI blood flow
Chronic gastritis
Ingestion of warm liquids/food
Accelerated emptying
Ingestion of carbonated liquids
Chronic alcoholism
Gastrectomy (gastric by-pass)

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

Physiology decreasing absorption

A

Decreased GI motility
Nausea (exclusive of vomiting)
Shock
Anticholinergics
Decreased GI blood flow
Fear, pain
Sympathomimetics
Delayed gastric emptying
Gastric fibrosis
Carcinomatosis
Smoking cigarettes

17
Q

Bariatric Surghery-gastric by pass

A

Most efficient method to tx morbid obesity
Complaints of increased sensitivity of reduced tolerance to EtOH as compared to pre-surgical state
Reduction in body weight [20 – 40% within 1-2 years]
Increased dose per Kg of body weight
Rapid absorption of EtOH
Higher Cmax
Earlier Tmax

18
Q

Is alcohol hydrophilic or hydrophobic

A

hydrophilic–

19
Q

Volume of Distribution

A

Volume of distribution is and expression of the total body water
Variability due to adiposity
Vd of alcohol decreases with age
Volume of Distribution
Males: 0.7 L/kg avg. 0.62-0.70 (.59-.9)
Females: 0.6 L/kg avg. .55-.66(.46-.86)

20
Q

Blood-tissue ratio

A

Whole blood consists mainly of water with red/white cells, proteins, lipids
DUI-whole blood
Hospital test on serum/plasma which runs higher