Components of DT

• Typical antipsychotics

  Disorder: schizophrenia

  Example: chlorpromazine

  • Binds to D2 receptors to block dopamine binding to + stimulating receptors in brain
  • Reduces positive symptoms such as hallucinations + delusions 
  • Knows as ANTAGONIST as it blocks usual function of particular chemical or substance
• Atypical antipsychotics

  Disorder: schizophrenia

  Example: clozapine

  • Dopamine ANTAGONIST
  • Blocks D2 receptors temporarily then rapidly disconnects
  • Allows more normal dopamine transmission
• Agonist substitution

  Disorder: addiction e.g. heroine

  Example: methadone

  • Binds to opioid receptors + activates them in similar way to heroin
  • Causes enough stimulation to reduce cravings for drug + prevents chance of withdrawal
  • Occupies opioid receptors sites for longer  to discourage use of other opioid drugs
  • Maintains opioid addiction is a safer way until addict can achieve abstinence
• Antagonist substitution

  Disorder: addiction e.g. alcohol

  Example: naltrexone

  • Binds to opioid receptors + blocks the effects of the addictive behaviour if used
  • Means if person engages in addiction they won’t get effect from it, including no increase in dopamine making the addictive behaviour less rewarding so addict less likely to engage
  • Reduces cravings as the addictive behaviour no longer leads to pleasure