Biological approach to treating OCD

Question 1

Which two types of drugs are used to treat OCD?

Answer 1

1. Anti-depressants
2. Anxiolytics (anti-anxiety drugs)

Question 2

What are three types of antidepressant drugs used to treat OCD?

Answer 2

1. Selective serotonin re-uptake inhibitors (SSRIs) – e.g. fluoxetine (brand name Prozac), sertraline (brand name Zoloft)
2. Tricyclics – e.g. clomipramine
3. Serotonin-noradrenaline/norepinephrine reuptake inhibitors (SNRIs) – e.g. venlafaxine

Question 3

How do SSRIs increase the levels of serotonin?

Answer 3

SSRIs inhibit the re-absorption (re-uptake) of serotonin in the pre-synaptic neuron, which then increases the concentration of serotonin at the synapse

Question 4

How do SNRIs treat OCD?

Answer 4

They block the transporter mechanism that re-absorbs both serotonin and noradrenaline in the pre-synaptic cleft after it has fired

Question 5

What is a disadvantage of using tricyclics?

Answer 5

They have more severe side effects than SSRIs

Question 6

How do anti-anxiety drugs work?

Answer 6

They reduce anxiety by slowing down the activity of the CNS by enhancing the activity of the neurotransmitter GABA (gamma-aminobutyric acid) – e.g. benzodiazepines (brand names Xanax, Valium and Klonopin)

Question 7

What are the two strengths of the biological approach to treating OCD?

Answer 7

Effectiveness- There is clear evidence for the effectiveness of drug treatments. Soomro et al. (2009) reviewed 17 studies comparing SSRIs to placebos (a substance that has no pharmacological value but controls for the belief that the pill you are taking will affect you) in the treatment of OCD. Found that SSRIs to be more effective than placebos in reducing the symptoms of OCD up to 3 months after treatment. Counter- Most studies on drug treatments are only of three to four months’ duration. There is a lack of long-term data regarding the effectiveness of drug therapy on OCD and so limits the credibility of the research.

Drug therapies are cost-effective and non-disruptive- Drug therapies require little input from the user in terms of effort and time. In contrast, therapies such as CBT require the patient to attend regular meetings and put considerable thought into tackling their problems. Also drug therapies are cheaper for the health service because they require little monitoring and cost much less than psychological treatments. These benefits mean that drug therapies are more economical for the health service than psychological therapies

Question 8

What are the three limitations of the biological approach to treating OCD?

Answer 8

Side effects- All drugs have side effects, not necessarily always severe but can be enough to make a patient stop taking the drug. - SSRIs = nausea, headaches and insomnia. - Tricyclics= side effects such as hallucinations and irregular heartbeat. These are only used in cases where SSRIs are not effective. - BZs= increased aggressiveness and long-term impairment of memory. These side effects limit the effectiveness of drugs as people stop taking the medication.

Not a lasting cure- Maina et al. (2001) found that patients relapse within a few weeks if medication is stopped. Koran et al. (2007)- comprehensive review of treatments for OCD suggested that, although drug therapy may be more commonly used, psychotherapies such as CBT should be tried first.

Publication bias- There is evidence of a publication bias towards studies that show a positive outcome of antidepressant treatment, –> exaggerating its benefits. It has been found that not only were positive results more likely to be published, but studies that were not positive were often published in a way that conveyed a positive outcome. Drug companies have a strong interest in the continuing success of psychotherapeutic drugs and much of the research is funded by these companies