reducing addiction: drug therapy

• agonists


  mimic the drug of dependence and acts as a substitute, they bind to neuron receptors and activate them, providing a similar effect, but not the same

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  same rewarding effects, but not as powerful - fewer harmful side effects and a longer-lasting effect

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  their main purpose is to stabilise the addict to control withdrawal symptoms, allowing for a gradual reduction in dose and symptoms
• nicotine replacement therapy (NRT) - agonists


  gradually releases nicotine via patch, gum, nasal spray, inhaler etc into bloodstream which binds with nicotinic acetylcholine receptors in the mesolimbic pathways, leading to the release of dopamine whilst avoiding tar, carbon monoxide and other poisonous chemicals present in tobacco smoke

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  nasal spray works the fastest but inhaler mimics the hand-to-mouth ritual of smoking - the best NRT is a combination of patches with a faster-acting form
• antagonists


  bind to opioid receptors and block them so the drug of dependence cannot have it's usual effect e.g., feelings of euphoria addicts crave to break to association between drug and reward

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  naltrexone may be used to stop the rewarding effects of heroin and alcohol, reducing the craving for them - it has also been trialled (not licenced) to treat gambling addiction as it taps into the same reward pathway
• aversives


  creates hypersensitivity to addictive substances such as alcohol through blocking the enzyme metabolising alcohol into a harmless acid, leading to a prolonged build up of it in the blood leading to severe hangover symptoms such as nausea, vomiting and headaches

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  it works through classical conditioning, with the aversive drug producing unpleasant consequences that becomes associated to the addictive substance, making it unappealing

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  one example of this is disulfiram
• research support


  Hartman-Boyce et al. (2018) - meta-analysis of high-quality research study into the effectiveness of NRT - found all forms of NRT significantly more effective in helping smokers to quit than both a placebo and no therapy - strong evidence that NRT can help people successfully stop smoking

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  issues in publication bias
• individual differences


  side effects - NRT often causes sleep disturbance, dizziness and headaches, with larger doses having worse side effects e.g., anxiety, depression -> poor treatment adherence

  aversives in particular are unpleasant to deal with

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  genetic variation - drugs do not work in the same way for everyone, single gene variations can respond more readily to treatments, implicating a need to make drug treatments more tailored to individual genetic profiles to increase effectiveness
• application/implications


  methadone as a substitute for heroin - administered medically with fewer risks from dirty needles or criminal sourcing, reducing cost to NHS due to HIV and reduced cost of policing and prosecuting drug-related crime

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  addiction can be viewed as a psychological weakness -> people reluctant to admit to an addiction (fear of judgement) and therefore treatment - drug therapy implies a neurochemical basis, reducing self-blame, making treatment easier to access

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  ethical issues in the form of humiliation from aversives and resultant poor treatment adherence
• debates


  reductionist nature of drug therapies - ignores psychological-socio-economic causes - only treats symptoms rather than cause
• alternatives


  CBT/behavioural interventions/AA more effective or an interactionist approach is more effective