treating OCD (biological approach)

• changing levels of neurotransmitters

  • drug therapy for mental disorders aims to increase or decrease levels of neurotransmitters in the brain or to increase/decrease their activity
  • low levels of serotonin are associated with OCD
  • => drugs work in various ways to increase the level of serotonin in the brain
• selective serotonin reuptake inhibitors (SSRIs)

  • SSRIs prevent the reabsorption and breakdown of serotonin in the brain
  • this increases its levels in the synapse and thus serotonin continues to stimulate the postsynaptic neuron
  • this compensates for whatever is wrong with the serotonin system in OCD
• typical dosage of SSRIs

  • a typical daily dose of fluoxetine (an SSRI) is 20mg although it may be increased if it is not benefitting the person
  • takes 3-4 months of daily use for SSRIs to impact upon symptoms
  • dose can be increased (eg 60mg a day) if this is appropriate
• combining SSRIs with CBT

  • drugs are often used alongside CBT to treat OCD
  • the drugs reduce a person's emotional symptoms (such as feeling anxious or depressed)
  • means they can engage more effectively with CBT
• alternatives to SSRIs

  • Tricyclics:
  • older type of antidepressants (such as clomipramine)
  • they have the same effect on the serotonin system as SSRIs but the side-effects can be more severe
  • SNRIs (serotonin noradrenaline reuptake inhibitors):
  • another class of antidepressant
  • like tricyclics = they are a second line of defence for people who don't respond to SSRIs
  • they increase the levels of serotonin as well as noradrenaline
• strength = studies show effectiveness

  • Soomro et al = reviewed 17 studies of SSRIs for the treatment of OCD
  • all 17 studies showed better outcomes following SSRIs than placebos
  • typically OCD symptoms reduce for around 70% of people taking SSRIs
  • means that drugs can be help to most people with OCD
• counterpoint to support for effectiveness

  • although drug treatments may be better than placebos, they may not be the most effective treatments
  • cognitive and behavioural (exposure) therapies may be more effective than SSRIs in the treatment of OCD
  • => drugs may not be the optimum treatment for OCD
• strength = drugs are cost-effective and non-disruptive

  • they are cheap compared to psychological treatments
  • => using drugs to treat OCD is good value for the NHS , also means that more people will have access to help
  • as compared to psychological treatments = SSRIs are also non-disruptive to people's lives
  • if you wish, you can simply take drugs until your symptoms decline, rather than spending time going to therapy sessions
  • means that many doctors and people with OCD prefer drug treatments
• limitation = drugs can have serious side effects

  • a minority of people taking SSRIs get no benefit
  • some people also experience side-effects:
  • such as: indigestion, blurred vision, loss of sex drive
  • for those taking clomipramine (tricyclic), side effects are more common and can be more severe:
  • more than 1 in 10 people = experience erection problems and weight gain
  • 1 in 100 = become aggressive
  • means that peoples quality of life is poor and the outcome is they may stop taking the drugs altogether, reducing the effectiveness of the treatment
• extra evaluation = biased evidence

  • some psychologists believe that the evidence for effectiveness is biased because of drug company sponsorship
  • HOWEVER = the best evidence available is supportive of the usefulness of drugs for OCD and evidence for psychological therapies can also be biased
  • means that as far as we know = drugs are helpful for treating OCD, so it may be preferable to continue using them