Biological approach treating OCD

• What is drug therapy?

  Treatment involving drugs that have a particular effect on the functioning of the brain or some other body system.

  • In the case of OCD, such drugs usually affect neurotransmitter levels.
• What is the antidepressant drug used to tackle the symptoms of OCD?

  SSRIs - Selective serotonin reuptake inhibitor.
• How do SSRIs work?

  • SSRis work on the serotonin system in the brain. Serotonin is released by certain neurons in the brain.
  • In particular it is released by the presynaptic neurons and travels across a synapse - the neurotransmitter chemically conveys the signal from the presynaptic neuron where it is broken down and reused.
  • By preventing the reabsorption and breakdown, SSRIs effectively increase levels of serotonin in the synapse and thus continue to stimulate the postsynaptic neuron.

  
• How is dosage of drug and other advice determined?

  • It varies according to which SSRI is prescribed.
  • Doses may increase if not benefitting the person - the drug is available as capsules or liquid.
• What are SSRIs often used alongside in order to treat OCD?

  Cognitive behaviour therapy.

  • The drugs reduce a person‘s emotional symptoms e.g. feeling anxious or depressed.
  • This means that people with OCD can engage more effectively with the CBT.
  • In practice some people respond best to CBT alone whilst others benefit more when additionally using drugs like fluoxetine.
• What happens if an SSRI isn’t effective after a few months?

  Dose can be increased or combined with other drugs:

  1. Tricyclics - acts on various systems including the serotonin system where it has the same effect as SSRIs. Some have more severe side-effects than SSRIs so it’s generally kept in reserve for those who don’t respond to SSRIs.
  2. SNRIs (serotonin-noradrenaline reuptake inhibitors) - a second, more recent line of defence for those who don’t respond to SSRIs.
• Evaluate a strength of drug treatment for OCD

  Evidence of effectiveness.

  • Soomro reviewed studies that compared SSRIs to placebos in the treatment of OCD.
  • All studies showed significantly better outcomes for SSRIs than for the placebo conditions - typically symptoms reduce for the majority of people taking SSRIs, and the remaining people can use alternative drugs or combinations of drugs.
• Evaluate a strength of drug treatment for OCD

  Cost-effective and non-disruptive.

  • Drug treatments are cheap compared to psychological treatments because many thousands of tablets or liquid doses can be manufactured in the time it takes to conduct one session of a psychological therapy.
  • Using drugs to treat OCD is therefore good value for public health systems like the NHS and represents a good use of limited funds.
• Evaluate a limitation of drug treatment for OCD

  Serious side effects.

  • Although drugs such as SSRIs help most people, a small minority will get no benefit.
  • Some people also experience side effects such as indigestion, blurred vision and loss of sex drive.
  • These side effects are usually temporary, however they can be quite distressing for people and for a minority they are long-lasting - this means that some people have a reduced quality of life as a result of taking drugs and may stop taking them altogether, meaning the drugs cease to be effective.