Agonist and Antagonist Substitution
Agonist and antagonist substitution
- Medication as treatment
- Given to people with substance use addiction
- Work at synapse level to alter behaviour
Agonist substitution: Methadone
- Used for opioid addiction (heroin)
- receptors become less sensitive, so less dopamine is released in the brain
- Methadone is synthetic
- Mimics the effect of heroin, but without the “high”
- Given orally, so blood concentrations rise and fall slowly
- Patients can gradually lower their dosage until they can stop taking it (detox and
abstinence)
Antagonist substitution: Naltrexone
- Used for opioid addiction (heroin)
- Used for addicts in recovery in order to prevent relapse
- Doesn’t activate receptors, no effect (makes drug less rewarding)
- Offered alongside psychological counselling to help prevent risk of relapse
- Can be used upto 6 months, only after withdrawal symptoms
Evaluation
1. Effectiveness
- Methadone lasts longer than heroin, allows person to separate themselves from negative
effects of drug abuse
Gowing et al (2001)
- Methadone programmes are very effective at reducing physical and social harms
- Longer someone is in treatment, better their outcomes and lower relapse chance
Marteau et al (2015)
- Buprenorphine is 6x safer than methadone
- Longitudinal study of 5 years
2. Ethical Implications
- Both drugs have side effects
- Just providing a quick fix
- Could be treating the symptoms rather than the cause
- Almost ignoring the mental illness
- Drug addicts who face prosecution may be pressured into treatment programmes
against their free will
3. Social Implications
- Reduction of the number of drug addicts
Agonist and antagonist substitution
- Medication as treatment
- Given to people with substance use addiction
- Work at synapse level to alter behaviour
Agonist substitution: Methadone
- Used for opioid addiction (heroin)
- receptors become less sensitive, so less dopamine is released in the brain
- Methadone is synthetic
- Mimics the effect of heroin, but without the “high”
- Given orally, so blood concentrations rise and fall slowly
- Patients can gradually lower their dosage until they can stop taking it (detox and
abstinence)
Antagonist substitution: Naltrexone
- Used for opioid addiction (heroin)
- Used for addicts in recovery in order to prevent relapse
- Doesn’t activate receptors, no effect (makes drug less rewarding)
- Offered alongside psychological counselling to help prevent risk of relapse
- Can be used upto 6 months, only after withdrawal symptoms
Evaluation
1. Effectiveness
- Methadone lasts longer than heroin, allows person to separate themselves from negative
effects of drug abuse
Gowing et al (2001)
- Methadone programmes are very effective at reducing physical and social harms
- Longer someone is in treatment, better their outcomes and lower relapse chance
Marteau et al (2015)
- Buprenorphine is 6x safer than methadone
- Longitudinal study of 5 years
2. Ethical Implications
- Both drugs have side effects
- Just providing a quick fix
- Could be treating the symptoms rather than the cause
- Almost ignoring the mental illness
- Drug addicts who face prosecution may be pressured into treatment programmes
against their free will
3. Social Implications
- Reduction of the number of drug addicts
