Substance Misuse

Question 1

What are the mechanisms of substance misuse and what are they the basis of

Answer 1

Tolerance - basis of dependence

Reward - basis of craving

Question 2

What is tolerance

Answer 2

Reduced responsiveness to drug caused by previous administration

Question 3

What drugs can you become tolerant too

Answer 3

Opioids
Ethanol
Barbiturates
Benzodiazepine

Question 4

What is dispositional tolerance

Answer 4

Less drug reaches active site
Decreased absorption
Increased metabolism
Increased excretion

Question 5

What is pharmacodynamic tolerance

Answer 5

Down regulation so less efficient or fewer receptors

Question 6

What does tolerance lead too

Answer 6

Withdrawal symptoms
Drug tries to return body to homeostasis when drug administered
When drug is stopped body’s response to combatting drug causes withdrawal symptoms
Often opposite to drug effect as body trying to do opposite

Question 7

Why does tolerance cause dependance

Answer 7

Body becomes dependent to avoid withdraw symptoms

Question 8

What is the reward pathway - where does it project

Answer 8

Neurones project from ventral segmental area to nucleus accumbens and cortex

Question 9

What happens when VTA stimulated

Answer 9

Dopamine is released

Causes sense of pleasure / reward

Question 10

What do drugs do

Answer 10

Heroin / cocaine / amphetamine
Can stimulate this pathway
Causing craving of reward feeling

Question 11

What will D2 antagonist do

Answer 11

Treat craving as blocks reward pathway but not dependence

Question 12

Why are some people more prone to addiction

Answer 12

Dopamine receptors can vary

Question 13

What do you do for drug addiction

Answer 13

Hx
21 day referral to services
BBV and urine drug screen
Follow up 
Possible methadone

Question 14

Who is high risk and may get faster referral

Answer 14

Neck injector
Pregnancy
Sex
Illness

Question 15

What do you need before starting methadone

Answer 15

ECG

Question 16

What can you say about methadone

Answer 16

Green liquid from pharmacy 
Dispensed daily 
Get heart tracing before
Do you use any other drugs
Any questions

Question 17

What is cocaine

Answer 17

A stimulant

Blocks uptake of NA, dopamine and serotonin

Question 18

How is it taken

Answer 18

Injected
Snorted
Smoked

Question 19

+ve effects

Answer 19

Stimulant 
Euphoria - dopamine
Alert
Energy
Confidence 
Decreased appetite
Decreased need for sleep

Question 20

-ve effects

Answer 20

Vasoconstrictor 
Raised BP
Resp failure
Cardiac arrhythmia - QT prolonged 
MI due to coronary vasospasm 
Aortic dissection 
Ischaemic colitis
Hyperthermia
Metabolic acidosis 
Rhabdomyolysis 
Tachy or Brady 
Paranoid psychosis
Financial / social

Question 21

What does cocaine do to pupils and what are withdrawal affects

Answer 21

Dilate

Depression
Irritable
Craving
Desire for food and sleep

Question 22

How do you Rx toxicity

Answer 22

Benzo = 1st line
Add GTN if chest pain then PCI if MI develops
Add sodium nitrprusside if high BP

Question 23

Amphetamine

Answer 23

Similar to cocaine but last longer

Toxic confusion, convulsions and death

Question 24

Examples of opiates

Answer 24

Opium
Morphine
Heroin 
Methadone
Codeine

Question 25

How can heroin be taken

Answer 25

Injected Snorted Smoked

Question 26

What does heroin do

Answer 26

``` Analgesia Drowsy Resp depression Cough reflex depression Causes 'a rush' N+V Decreased sympathetic - Brady / hypotension Decreased body temp Constipation Viral infection - hep B / C / HIV by sharing needles Bacterial infection - IE / SA / necrotising fascitis/ sepsis VTE Social issues ```

Question 27

What is characteristic sign of overdose

Answer 27

Respiratory arrest with a pulse

Question 28

What are other signs

Answer 28

Pinpoint pupils Resp <8 Braydcardia Hypotension

Question 29

How do you Rx overdose

Answer 29

Nalaxone

Question 30

What are symptoms of withdrawal

Answer 30

``` Craving Insomina Muscle pain Dilated pupils Increased gland secretion ```

Question 31

What is methadone

Answer 31

``` Long term opiate to decrease craving Can also use bupronephrine Decriminaise drug use Reduce IV Compliance monitored using urinalysis ```

Question 32

What is ecstasy

Answer 32

MDMA

Question 33

What does ecstasy cause

Answer 33

``` Same as cocaine / LSD Dilated pupils Tachycardia High BP Hyperthermia Hyponatraemia Dehydration Liver and brain cell damage ``` Rx = supportive or dantrolene if hyperthermia

Question 34

What is psychoactive agent in cannabis

Answer 34

THC

Question 35

What are affects of cannabis

Answer 35

``` Relax Increased sociable Increased appetite Change in time Merging of senses - synaesthesi ```

Question 36

What does high THC cause

Answer 36

``` Anxiety Persecutory ideation Hallucination Rest issue Exacerbate mental illness ```

Question 37

What are novel psychoactive substances

Answer 37

Legal high

Question 38

When are anabolic (androgenic) steroids prescribed

Answer 38

Hypogonadism Muscular dystrophy AIDs wasting

Question 39

What are SE

Answer 39

``` Muscle hypertrophy Acne Stretch marks Feminisation Hypogonadism Gynaecomastia Virilisation Growth Cholesterol BP Liver Mania ```

Question 40

What is Virilisation

Answer 40

``` Hirsutism Deep voice Clit enlargement Menstrual irregularity Thin hair ```