Substance misuse and Alzheimer's

Question 1

What type of drug order elimination does alcohol undergo?

Answer 1

Zero order elimination

Question 2

What is zero order elimination?

Answer 2

In zero-order kinetics, the rate of drug elimination is constant regardless of the concentration of the drug in the body.

Example: Alcohol metabolism follows zero-order kinetics. No matter how much alcohol is consumed, the body can only metabolize it at a certain rate per unit of time.

Question 3

What are the inhibitory actions that occur with alcohol consumption?

Answer 3

Potentiates inhibitory GABA

Inhibits excitatory glutamate

Question 4

What are the excitatory actions that occur with alcohol withdrawal?

Answer 4

Restlessness

Tremor

Anxiety

Tachycardia/hypertension

Seizures

Delirium tremens (confusion/hallucinations) = EMERGENCY

Question 5

What is the typical timeframe for delirium tremens?

Answer 5

As early as 48 hours after abrupt cessation of alcohol in those with chronic use and can last up to 5 days.

Question 6

A build up of what substance results in alcohol hangover?

Answer 6

Acetaldehyde

Question 7

Alcohol is inhibitory and alcohol withdrawal is excitatory meaning that alcohol withdrawal should be treated with inhibitory medications. True/false?

Answer 7

True

Question 8

Excitatory features associated with an alcohol withdrawal state?

Answer 8

Restlessness

Tremor

Anxiety

Tachycardia/hypertension

Seizures

Delirium tremens

Question 9

What inhibitory medications are used in alcohol withdrawal?

Answer 9

Benzodiazepines
Diazepam (long acting) = preferred
Lorazepam (short acting) = if acute (e.g. DT-delirium tremens)

Carbamazepine
If benzos contraindicated

Clomethiozole
3rd line (respiratory depression if taken with alcohol)

Question 10

When are benzodiazepines contraindicated?

Answer 10

Because of their muscle relaxant action, benzodiazepines may cause respiratory depression in susceptible individuals.

So contraindicated in:
Myasthenia gravis
Sleep apnea
Bronchitis
COPD

Question 11

Differences in features between Wernicke’s encephalopathy and Korsakoff syndrome?

Answer 11

Wernicke: acute thiamine deficiency (ataxia, nystagmus, confusion),

Korsakoff: chronic thiamine deficiency (dementia, confabulation)

Question 12

What are confabulations in Korsakoff syndrome?

Answer 12

Fabrication of imaginary experiences as compensation for loss of memory.

Question 13

What are symptoms of opiates?

Answer 13

Analgesia

Sedation

Euphoria

Constipation

Nausea

Question 14

What are features of opiate toxicity?

Answer 14

Unconsciousness

Respiratory depression (slow or shallow breathing causing poor gas exchange in alveoli).

Pin point pupils (constricted pupils)

Question 15

What drug is used to reverse opioid toxicity?

Answer 15

IV naloxone

Question 16

What are options for opiate substitution therapy?

Answer 16

Methadone:
Full mu opioid agonist
Oral solution

Buphrenorphine:
Partial mu opioid agonist
Oral tablet

Question 17

What are the main hallmark’s of Alzheimer’s dementia?

Answer 17

Cortical atrophy (wide sulci and narrow gyri).

Neurofibrillary tangles (abnormal tau protein accumulation in the neurons).

Senile plaques (polymorphous beta-amyloid protein deposits found in the brain in Alzheimer disease and normal aging).

Question 18

Features of opiate intoxication?

Answer 18

Drowsiness

Confusion

Decreased respiratory rate

Decreased heart rate

Constricted pupils

Track marks (needle marks) - applies if IV route has been used.
- Abscess at injection sites
- Veins thrombosed and damaged causing difficulties with IV access.

Question 19

Opiate withdrawal is life threatening. True/false?

Answer 19

False

Unlike alcohol withdrawal, opiate withdrawal is NOT life threatening.

Question 20

What are some of the features of opiate withdrawal?

Answer 20

Agitation

Anxiety and irritability

Chills

Runny nose

Piloerection (“goosebump” hairs)

Dilated pupils

Increased blood pressure and heart rate

GI disturbances (i.e. abdominal cramps, nausea, vomiting and diarrhoea).

Question 21

During opiate withdrawal, what drugs can help to treat symptoms?

Answer 21

Methadone: may cause prolonged Qtc

Loperamide (for diarrhoea)

Anti-emetics (for nausea

Question 22

When does alcohol withdrawal symptoms usually become apparent?

Answer 22

Onset usually 12 hours after last drink.

Question 23

Characteristic features of alcohol withdrawal?

Answer 23

Nausea and vomiting

Tremor

Sweating

Anxiety

Agitation

Question 24

What is delirium tremens and when does it usually occur?

Answer 24

A life threatening medical emergency, and usually occurs at day 3 of withdrawal, and lasts 3 days

Question 25

What are characteristic features of delirium tremens?

Answer 25

Characterised by: Paranoid delusions Visual/auditory and classically haptic (tactile) hallucinations (sensation of crawling e.g. formication) Seizures

Question 26

What is typical management of delirium tremens?

Answer 26

Oral lorazepam as first line, and if the oral route cannot be used for whatever reason, parenteral lorazepam or haloperidol.

Question 27

What is used for prevention and treatment of alcohol withdrawal?

Answer 27

Short-acting benzodiazepines i.e. chlordiazepoxide and oxazepam (if evidence of liver injury).

Question 28

What is supportive treatment of alcohol withdrawal?

Answer 28

Fluids Anti-emetics Thiamine (i.e. pabrinex) - which is vitamin B1

Question 29

What does wernicke-korsakoff cause in the brain?

Answer 29

Mammiliary body atrophy

Question 30

What is Wernicke's encephalopathy?

Answer 30

Reversible presentation (treated with high dose IV thiamine e.g. pabrinex).

Question 31

Characteristic features of Wernicke's encephalopathy?

Answer 31

Confusion Ataxia Ophthalmoplegia Nystagmus Less clinical features include: urinary incontinence and hypothermia due to autonomic neuropathy.

Question 32

What is Korsakoff's psychosis?

Answer 32

An irreversible manifestation of untreated Wernicke's encephalopathy.

Question 33

Characteristic features of Korsakoff's psychosis?

Answer 33

Retrograde amnesia (loss of memory before incident) Anterograde amnesia (inability to make new memories) Confabulations (fabricate imaginary experiences as a compensation for memory loss)