Methods Of Modifying Behaviour 1: Agonist And Antagonist Flashcards
What are the two categories of drugs used to treat addiction?
Agonist and antagonist
What is an agonist?
An agonist is a chemical that binds to a postsynaptic receptor and actives that receptor to produce a response, in the case of medications, agonists are designed to imitate the action of another substance
(E.g methadone for heroin)
What is methadone used for treating (agonist) ?
To treat addictions to opioid drugs like heroin, its synthetically produced to mimic some of the effects of heroin
How is Methadone used?
It is used a part of maintenance treatment, the aim is that by giving heroin users methadone, it will reduce cravings and prevent withdraw symptomps, it has some of the same effects of heroin but doesn’t mimic the high.
It should be reduced over time (detoxification) until the individual stops completely (abistenence)
How does the dosage of Methadone work?
NICE guidelines in the UK suggest an inital dose of 10-40 mg daily, which is increased by 10mg daily until no withdraws are seen. Matinence is usually 60-120 mg a day, dose is eventually reduced until abstienence is reached
A Dr, nurse of pharmasist see’s the patient each day for the 1st 3 months of treatment until they can continue without supervision.
What does NICE stand for?
National Institute Of Care Excellence
Why does a healthcare professional oversee the administration of Methadone for the 1st 3 months?
To make sure the dosage is correct, ensuring patients don’t take multiple doses and to ensure the Methadone isn’t being sold on to other drug users
What is an antagonist?
An antagonist binds to a receptor but rather than causing a reaction, it blocks the usual function of a particular substance
What is Naltrexone used for? (Antagonist)
Primarily in the abstinence stage of recovery from opioid or alcohol addiction
How is Naltrexone used (opiods)?
Accourding to NICE guidlines, it should be given to people who have stopped taking opioids and have demonstrated that they are highly motivated to stay free from drugs. It blocks the euphoric and pleasurable effects of opioids and makes them far less rewarding
How is Naltrexone admisteted?
By an implant of depot injection
How is Naltrexone used (alcohol)?
Recommended alongside psychological intervention and should be used after withdrawal from alcohol has occurred, it can be used for up to a 6 month period and users should be kept under supervision to check they have not started drinking again
What are the three evaluation points of effectiveness for agonist and antagonist substitution?
Effectivness of Methadone
Comparing Methadone and Buprenorphine
Effectivness of Naltrexone
Explain the effectiveness of Methadone (evaulation)
NICE assessed 31 reviews of its effectiveness, including 27 randomised control trials, they found higher levels of retention for those taking methadone than a placebo, subsequent research has also claimed that methadone is an effective maintenance treatment if the dose is correct
Compare Methadone to Buprenorphine (evaluation)
Buprenorphine is an alternative to Methadone, its milder and has agonist and antahonist properties as it blocks the euphoria. Research has found that its 6x safer than Methadone as it has a lower risk of overdoes, however methadone is preferred as its more effective at retaining patients
Explain the effectiveness of Naltrexone (evaulation)
NICE reviwed 17 studies concerning Naltrexones effectivness at treating a heroin addiction, it was associated with a lower relapse rate , espically in highly motivated individuals and those who were closely monitored and offered extra support
What are two ethical implications of agonist and antagonist subsitition?
Ethical crisitisms of Methadone and the side effects of Naltrexone
What are two social implications of agonist and antagonist subsitition
The financial cost of Methadone to society and Methdones link to criminality
Explain the ethical criticisms of the use of Methadone (ethical implications)
Methadone can interfer with other drugs such as antidepressants and cause respiritory issues.
There is also a danger of overdose, ONS reported 429 methadone overdose deaths in 2013
Methadone could also create another addiction, many remain on methadone for a long period, which may make it harder to reach detoxification and abstinence
Explain the side effects of Naltrexone (ethical implications)
Naltrexone has been linked to a great risk of overdose. As if an invidual beings to take the drug they once did again, they may need to make more to get the same ‘high’
Liver function also needs to be closely monitored if on Naltrexone
Explain the financiall cost of Methadone to society (social implications)
The Center For Policy Studies called prescribing Methadone an ‘expensive failure’ not only for the actual drug but for the 320,000 problem drug users on benifits which tax payers are paying for
Explain Methadone’s link to criminality (social implications)
A report by the National Treatment Agency (2009) claimed that Methadone had an immediately positive effect on reducing criminality, suggesting that offending rates reduce by half when addicts are in treatment, less criminality is better for society
