Addiction- modification antagonist and agonist substitution

Question 1

How do these work?

Answer 1

Mimic or block the effects of particular substances on the brain

Question 2

What do agonist drugs do?

Answer 2

Enhances activity
An agonist is a chemical that binds to a postsynaptic receptor and activates that receptor to produce a response. In the case of medication, agonists are designed to imitate the action of another substance such as heroin.

Question 3

What do antagoist drugs do?

Answer 3

Block receptor sites

Question 4

What is the agonist substitution?

Answer 4

Methadone

Question 5

What does methadone agonist do?

Answer 5

Used during an addiction to opioid
When users take heroin it causes an excess of dopamine meaning receptor sites become less sensitive. Thus neurons adapt to high levels of dopamine by releasing less so less pleasurable effect and avoidance of withdrawal

Question 6

What is methadone?

Answer 6

Replacement for heroin
This occupies the dopamine receptors in the brain mimicking the heroin without the high activating dopamine receptors so reducing the symptoms of withdrawal
-Thus meaning it doesn’t have the same euphoric rush that’s associated with jerion (meaning patients don’t have extreme highs and lows)
-So they will become addicted to methadone and not extremience uncontrolled compulsivity
-Given orally so blood concentration with rise and fall slowly vs crash and rush of injective heroin

Question 7

What happens after methadone have stabilised withdrawal symptoms?

Answer 7

Patient gradually lowers their dosage via detoxification until they can abstained from it

Question 8

Why is methadone given orally?

Answer 8

-Given orally so blood concentration with rise and fall slowly vs crash and rush of injective heroin

Question 9

What is the recommended dosage for methadone/

Answer 9

10-40mg per dosage
Interested by up to 10 mg daily until no signs of withdrawal are seen

Question 10

What is the antagonist substance?

Answer 10

Naltrexone

Question 11

Antagonist Naltrexone- what is this?

Answer 11

Used in opioid addictions
Used for addicts in recovery to prevent relapse unlike methadone that manages withdrawal symptoms

Question 12

Antagonist Naltrexone- what biological action is taken?

Answer 12

Blocks dopamine receptor sites so dopamine can bind

Question 13

Antagonist Naltrexone- what effect does this have on feelings produced by drugs?

Answer 13

No pleasurable feeling so not rewarding

Question 14

Antagonist Naltrexone- who is this given to?

Answer 14

People who can relapse

Question 15

Antagonist Naltrexone- How is this given?

Answer 15

Liquid and tablets

Question 16

Antagonist Naltrexone- what addictions can it be used for?

Answer 16

Opioid
Meth

Question 17

Evaluation- effectiveness NICE methadone?

Answer 17

Viewed 31 people for methadone using 27 randomized controlled trials
-Find that people on methadone stayed on study whole way through and had low use of illegal drug use compared to those in placebo that dropped out

Question 18

Evaluation- effectiveness Van den Brink and Hassans 2006 meta analysis?

Answer 18

Conducted a meta analysis of studied into the effectiveness of a range of treatment conducted that as long as the dosage adequates then methadone is effective as a maintenance treatment

Question 19

Evaluation effectiveness- what is buprenorphine?

Answer 19

Milder medication that’s both agonist and antagonist that partially activates dopamine receptors reducing the withdrawal symptoms but also blocking receptors preventing euphoria associated with opioids
-Reduced change of overdose due to the ceiling effect, meaning large quantities of drug will not produce greater effect

Question 20

Buprenorphine Marteau et al study?

Answer 20

Longitudinal study finding buprenorphine is 6x safer than methadone looking at the death
-2366 deaths methadone vs 52 buprephonine

Question 21

Buprenorphine- Whelan and Remski?

Answer 21

Person with an addiction may prefer the feeling from methadone and are more likely to continue with treatment

Question 22

Evaluation- effectiveness of naltrexone NICE?

Answer 22

17 studies looking at heroine addicts
Randomised trial showed no significant difference between naltrexone and control treatment on the treatment programme
-When results pooled drug was associated with a reduction in relapse in rats, especially those closely monitored and offering extra support

Question 23

Evaluation- effectiveness of naltrexone Lahti et al?

Answer 23

Effectiveness of naltrexone on small sample of gamblers, instructed to take it before gambling or when they felt the urge to
Finding it significant decrease in gambling levels although they highlight that further researchers need

Question 24

Evaluation- Naltrexone Gowing et al?

Answer 24

Not appropriate for all drug users, addicts need to have completely stopped taking heroin due to withdrawal symptoms occurring
-Drug only affective with highly motivated
-Thus meaning high attrition rate so bias sample

Question 25

Evaluation- ethics side effects of methadone?

Answer 25

Confusion Dizziness Changes in heartbeat Tremors Seizures Anxiety

Question 26

Evaluation- ethics dangers of methadone?

Answer 26

Can interact with other drugs like alcohol and antidepressant to cause respiratory problems Dangers of overdose 2023- deaths 209

Question 27

Evaluation- risks of naltrexone?

Answer 27

Unethical as it can create another addiction Monitoring liver issues If person is still opioid dependant taking this may cause withdrawal symptoms and displace opioids still in receptors

Question 28

Evaluation- ethics counter argument?

Answer 28

Do side effects outweigh addiction?

Question 29

Evaluation- social implication?

Answer 29

Economy= can addicts be in work, cant contribute to economy Healthcare- strain on NHS, funding methadone when we aren't 100 sure its effective Society- reducing addiction, better society, more people in work and better economy

Question 30

Evaluation- social implication the national treatment agency?

Answer 30

Treating heroin users with methadone is positive as it reduces criminality suggesting rates of offending are reduced by half when addicts are in treatment

Question 31

Evaluation- social implication Gyungell?

Answer 31

Drug related reoffending has continued to rise despite the availability of drug treatment like methadone, possible problem is that by availability of drug treatment like methadone Possible problems is that by settings up methadone program centered on particular place and people concerned about possible increase in crime and antisocial behaviour in neighbourhood

Question 32

Evaluation- social implication what did the the advisory council for the misuse of drugs and the environment?

Answer 32

People who are disadvantaged are more likely to overdose as they dont have the sufficient recourses to get help for overdose

Question 33

Evaluation- cost effectiveness Gyungell?

Answer 33

Prescribing methadone was an expensive failure and cost society's money, not only for methadone but the 320,000 problem drug users benefit greater success would be achieved by funding rehab until encourages justice

Question 34

Evaluation- cost effective Doward?

Answer 34

Charity drug scope has distribution the claims made in the report, says it overstimulate the cost of prescribing methadone