Alcohol

Question 1

Properties of alcohol

Answer 1

1) colourless
2) clear
3) Boiling point = 78 C
4) Volatile
5) Soluble in water
6) Vaporizing

Question 2

How is alcohol produced?

Answer 2

Alcohol is produced through fermentation, where sugar is converted into alcohol and CO₂ by microorganisms like yeast.

Question 3

How much alcohol is obtained from sugar fermentation?

Answer 3

100 mg of sugar produces approximately 51.2 mg of alcohol.

Question 4

What happens when alcohol concentration increases during fermentation?

Answer 4

Fermentation is self-limiting, as alcohol inhibits the process once concentrations reach 12–15%.

Question 5

What are the main stages of alcohol metabolism?

Answer 5

Absorption – Alcohol is absorbed rapidly through the gastrointestinal tract.

Distribution – Alcohol is distributed throughout the body’s water compartments.

Metabolism & Elimination – Processed mainly in the liver, alcohol is eliminated at a rate of grams per 100 milliliters (mass/volume).

Question 6

List the ethanol dosage forms

Answer 6

Beer, wine, meat, spirits, cocktails and mixed drinks

Question 7

route of administration of alcohol

Answer 7

Oral
intravenous
rectal
inhalation(lungs)

Question 8

Processes after administration

Answer 8

Pharmacokinetics
absorption
distribution
metabolism
Excretion

Question 9

Effects of pharamcodynamics

Answer 9

Excitement
Relaxation
disinhibition
Euphoria
(This is is when Blood and alcogol concentraion is approxiamately 50mg%)

Question 10

Result of alcohol effects

Answer 10

• antaxia
• incoordination
• unconciousness
• coma
• death (BAC is greater than 400mg%)

Question 11

What is Widmark’s formula used for?

Answer 11

It estimates total alcohol mass in the body based on weight and blood alcohol concentration (BAC).

Question 12

Widmark’s formula

Answer 12

A=p xc x r x10

A=total mass of alcohol in g
p=mass of person in kg
c=concentration of alcohol in blood in g/100ml
r=distribution factor
10=factor to change from 0/00 to %

Question 13

What is Winek’s formula used for?

Answer 13

It provides an alternative approach to calculating alcohol distribution and metabolism.

Question 14

How is alcohol absorbed in the alimentary canal?

Answer 14

Alcohol is absorbed through diffusion.

Minimal absorption occurs in the mouth and oesophagus.

The stomach absorbs about 20% of ingested alcohol.

The small intestine absorbs about 80% due to its large surface area.

Question 15

What factors influence alcohol absorption?

Answer 15

• Surface area of mucous membrane.
• Absorption capacity of the mucous membrane.
• Peristaltic movement of the gastrointestinal tract.
• Functional status of the pyloric sphincter.
• Nature, composition, amount, and strength of the beverage consumed.
• Contents of the gastrointestinal tract (food slows absorption).
• Presence of medicines or other chemical substances.

Question 16

Can alcohol be absorbed through the airways and lungs?

Answer 16

Yes, absorption occurs via the mucosa of the trachea, bronchi, and alveoli, but alcohol is highly irritating to lung tissues.

Question 17

Can alcohol be absorbed through the skin?

Answer 17

No, due to low lipid solubility, alcohol is not absorbed through intact skin.

Question 18

Can alcohol be administered via intravenous (IV) or subcutaneous (SC) injection?

Answer 18

IV administration is theoretically possible but not common.

SC injection causes local pain and irritation, and absorption is poor due to vasoconstriction.

Question 19

How does alcohol circulate through the body?

Answer 19

Absorbed alcohol moves from the stomach and small intestine into the bloodstream.

It spreads throughout the rest of the body based on several factors:

• Cardiac output (blood circulation efficiency).
• Water content of organs (higher water content leads to greater distribution).
• Blood supply (organs with strong blood flow receive more alcohol).
• Speed of diffusion (depends on concentration gradients).

Question 20

How much alcohol is metabolized in the liver?

Answer 20

85–90% of alcohol is metabolized in the liver.

Question 21

What is the rate of alcohol metabolism?

Answer 21

Fasted individuals: 10–15 mg/100ml/h.

Non-fasted individuals: 15–20 mg/100ml/h.

Physiological range: 10–35 mg/100ml/h.

Question 22

Where is the remaining alcohol eliminated?

Answer 22

The remaining alcohol (unchanged) is excreted via the lungs, kidneys, and sweat

Question 23

How does alcohol get broken down in the body?

Answer 23

Alcohol undergoes a two-step enzymatic breakdown:

1. Alcohol → Acetaldehyde
   * Alcohol dehydrogenase (ADH)
   * Nicotinamide adenine dinucleotide (NAD)
   * Catalases
2. Acetaldehyde → Acetic Acid
   * Acetaldehyde dehydrogenase (ALDH)
   * Oxidases
   * Lyases

Question 24

What is MEOS (Microsomal Ethanol Oxidation System)?

Answer 24

MEOS is an alternative pathway that enhances alcohol metabolism, particularly at high alcohol concentrations

Question 25

Do females metabolize alcohol faster than males?

Answer 25

Studies suggest that females eliminate alcohol at a faster rate due to differences in liver-to-body weight ratio and enzymatic activity.

Question 26

What is the partition factor for breath and blood alcohol?

Answer 26

The standard partition ratio is 2300:1, meaning 1 part alcohol in breath corresponds to 2300 parts in blood.

Question 27

What factors influence breathalyzer results?

Answer 27

Breathalyzer machine calibration. Medical conditions affecting breath output. Partition factor variability among individuals. Single-use limitations. Breathing pattern, which affects alcohol concentration in expelled air.

Answer 28

* Central Nervous System (CNS) Acts as a suppressant, slowing neural activity. Mellanby Effect – Behavioral impairment is greater when BAC is rising than when it is falling. * Eyes Pupil dilation. Slower reaction times. Tunnel vision. Red conjunctiva (eye irritation). * Cardiovascular System (CVS) Increased pulse rate. Vasodilation (blood vessel expansion). * Kidneys Diuretic effect (increased urination). Suppression of ADH (antidiuretic hormone), leading to fluid loss. * Endocrine System Increase in adrenaline (A) and noradrenaline (NA). Hypoglycemia (lowered blood sugar levels). * Sexual Function Alcohol "provokes the desire, but takes away the performance."

Question 29

How can alcohol be produced post-mortem?

Answer 29

Enzymes act on carbohydrates, leading to post-mortem alcohol production, which must be distinguished from ante-mortem alcohol levels.

Question 30

What factors influence post-mortem BAC accuracy?

Answer 30

* Terminal hyperthermia. * Sepsis. * Ambient temperature at the body’s storage location. * Trauma, which may affect fluid distribution.

Question 31

How can ante-mortem vs. post-mortem alcohol levels be compared?

Answer 31

Vitreous humour-to-blood ratio. Urine Ethanol Concentration (UAC) vs. Blood Alcohol Concentration (BAC) ratio.

Question 32

effect of 0.00–0.05 g% BAC level

Answer 32

No abnormalities in most people. Loss of inhibition. Reaction time slowed (2×).

Question 33

effect of 0.05–0.10 g% BAC level

Answer 33

* Emotional lability (unstable mood). * Memory impairment. * Disorientation to time, place, person (TPP).

Question 34

effect of 0.15–0.25 g% BAC level

Answer 34

* Speech abnormalities. * Emotional instability. * Balance impairment and memory loss.

Question 35

Effect of 0.25–0.35 g% in BAC

Answer 35

* Complete loss of muscle coordination. * Apathy/stupor. * Memory loss.

Question 36

Effect of >0.35 g% in BAC

Answer 36

* Stupor followed by coma. * Depression of vital centers. * Death.

Question 37

What are key principles for specimen collection?

Answer 37

Check container expiry date. Ensure container integrity. Note the seal number for chain of custody.

Question 38

What specimen types are commonly collected?

Answer 38

* Blood. * Gastric contents. * Bile. * Urine. * Saliva. * Breath. * Tissue samples. * Synovial fluid.

Question 39

What are the legal blood alcohol concentration (BAC) limits for drivers in South Africa?

Answer 39

General drivers: 0.05 g/100 ml. Professional drivers (as per Section 32): 0.02 g/100 ml.

Question 40

What are the legal breath alcohol concentration (BrAC) limits for drivers?

Answer 40

General drivers: 0.24 mg/1000 ml. Professional drivers: 0.10 mg/1000 ml.

Question 41

What activities are prohibited when over the legal BAC/BrAC limits?

Answer 41

Driving a vehicle on a public road. Occupying the driver’s seat while the engine is running.

Question 42

What changes to the alcohol limits for drivers are being discussed in parliament?

Answer 42

BAC limit would be reduced from 0.05 g/100 ml to 0.00 g/100 ml. BrAC limit would be reduced from 0.24 mg/1000 ml to 0.00 mg/1000 ml.

Question 43

What does Section 37 (2)(a) and (b) of the Criminal Procedure Act regulate?

Answer 43

It governs the taking of blood specimens for legal and forensic purposes, particularly in cases involving suspected intoxication while driving.