biological approach to treating OCD

• Drug therapy for mental disorders


  Aims to increase or decrease levels of neurotransmitters in the brain or to increase/decrease their activity
• SSRIs


  Selective serotonin reuptake inhibitors, the standard medical treatment used to tackle the symptoms of OCD
• How SSRIs work


  1. Serotonin is released by presynaptic neurons and travels across a synapse

  2. Serotonin chemically conveys the signal from the presynaptic neuron to the postsynaptic neuron

  3. Serotonin is then reabsorbed by the presynaptic neuron where it is broken down and reused

  4. SSRIs prevent the reabsorption and breakdown of serotonin, effectively increasing levels in the synapse and continuing to stimulate the postsynaptic neuron
• Typical daily dose of fluoxetine (e.g. brand name Prozac)

  20 mg, may be increased if not benefitting the person
• Time for SSRIs to have much impact on symptoms

  Three to four months of daily use
• Combining SSRIs with other treatments

  • Drugs are often used alongside cognitive behaviour therapy (CBT) to treat OCD
  • Drugs reduce a person's emotional symptoms, allowing them to engage more effectively with the CBT
• Alternatives to SSRIs


  • Increase SSRI dose (e.g. up to 60 mg a day for fluoxetine)
  • Combine SSRI with other drugs
  • Try different antidepressants
• Tricyclics


  • Act on various systems including the serotonin system, have more severe side-effects than SSRIs, generally kept in reserve for people who do not respond to SSRIs
• SNRIs


  • Increase levels of serotonin as well as another different neurotransmitter - noradrenaline, a second line of defence for people who don't respond to SSRIs
• strength of drug treatments for OCD


  • good evidence for its effectiveness.

  • E.g. Mustafa Soomro reviewed 17 studies that compared SSRIs to Placebo in the treatment of OCD.

  • All 17 studies showed significantly better outcomes for SSRI, than for the placebo conditions.

  • Symptoms reduce for 70% of people taking SSRI and remaining 30% can be helped by either alternative drugs and therapies.

  • Means that the drugs appear to be helpful for most people with OCD.
• Limitation of drug therapies for OCD


  • the drugs can have potentially serious side effects.

  • The side-effects are usually temporary, but can be distressing for people or long-lasting.

  • for those taking tricyclic clomipramine, side-effects, or more common and serious.

  • For example, 1 in 10 can experience erection problems and weight gain and 1 in 100 can become aggressive experience, heart related problems.

  • means that some people might have a reduced quality of life as a result of taking the drugs.