10. The Biological Approach To Treating OCD

Question 1

What is serotonin?

Answer 1

A neurotransmitter implicated in many behaviours and physiological processes, including eating, sleeping and depression.

Question 2

What is drug therapy?

Answer 2

The treatment of OCD through chemical means - such drugs usually affect neurotransmitter levels.

Question 3

What does therapy for mental disorders aim to do?

Answer 3

It’s aims to increase or decrease levels of neurotransmitters in the brain to increase/decrease their activity.

Question 4

What are SSRIs?

Answer 4

Selective serotonin reuptake inhibitors - antidepressants

Question 5

What are antidepressants used for in people with OCD?

Answer 5

They are used to reduce the anxiety associated with OCD

Question 6

Name two SSRIs

Answer 6

Prozac and Paxil

Question 7

How do SSRIs work?

Answer 7

SSRIs work by blocking the reuptake (reabsorption) of serotonin at the pre-synaptic neuron after it has fired.

By preventing the reabsorption it has the effect of increasing levels of serotonin at the synapse, prolonging its activity and increasing stimulation to the receiving neuron.

This increase in levels of the neurotransmitter has the effect of regulating mood and anxiety. (Back to normal)

Question 8

What is the typical dosage of antidepressants?

Answer 8

A typical daily dosage of Prozac is 20mg, but this may increased if it is not benefitting the patient.

Question 9

How long does it take for the daily use of SSRIs to impact upon symptoms?

Answer 9

3-4 months

Question 10

What type of therapy are drugs often used alongside to treat OCD?

Answer 10

Drugs are often used alongside cognitive behavioural therapy (CBT) to treat OCD. The drugs reduce the patient’s emotional symptoms, such as feeling anxious or depressed. This means that patients can engage more effectively with CBT.

Question 11

When an SSRI is not effective after 3-4 months the dose can be increased it it can be combined with other drugs. Sometime different antidepressants are tried.

What are these antidepressants called?

Answer 11

Tricyclics

Question 12

Name a tricyclic

Answer 12

Clomipramine

Question 13

How do trycyclics work?

Answer 13

They work in exactly the same way as SSRIs but block the reabsorption noradrenaline as well as serotonin (this works on levels of both dopamine and serotonin). It blocks the reabsorption of both the chemicals into the pre synaptic neuron after it has fired. As a result, mode of both of these neurotransmitters are left in the synapse, prolonging their activity.

Question 14

What are the advantages and disadvantages of tricyclics compared to SSRIs?

Answer 14

Tricyclics have the advantage of targeting more than one neurotransmitter. However, they have greater side effects than SSRIs so are used as a second-line treatment when SSRIs are not effective.

Question 15

If a patient fails to respond to SSRI or Clomipramine some patients may also be prescribed an antipsychotic medication. Name one.

Answer 15

Risperidone

Question 16

What effect do antipsychotic drugs have?

Answer 16

These drugs have dopamine lowering effect that have proven useful in reducing depressions and anxiety symptoms in people with OCD whose symptoms have not responded to an SSRI alone.

Question 17

What is a placebo?

Answer 17

A sugar substitute of a drug that contains none of the actual drug.

Question 18

EVALUATION OF DRUG THERAPY

Give two strengths of drug therapy

Answer 18

• a strength of drug therapy is that it is effective at tackling OCD symptoms
• a strength is that drugs are cost-effective and non-disruptive

Question 19

EVALUATION OF DRUG THERAPY

Explain the strength of drug therapy in that it is effective at tackling OCD symptoms

Answer 19

For example, Soomro et al reviewed 17 studies comparing SSRIs to placebos in the treatment of OCD. All 17 studies showed significantly better results for SSRIs than for the placebo conditions.

Effectiveness is greatest when SSRIs are combined with a psychological treatment, usually CBT. Typically symptoms reduce for around 70% of patients taking SSRIs, the rest are helped by alternative drugs or CBT + drugs.

So drugs can help most patients with OCD which is strength.

Question 20

EVALUATION OF DRUG THERAPY

Explain the strength of drug therapy in that it is cost effective and non-disruptive

Answer 20

A strength of drug treatments in general is that they are cheap compared to psychological treatments. Using drugs to treat OCD is therefore good value for the NHS. As compared to psychological therapies SSRIs are also non-disruptive to patients’ lives. If you wish you can simply take drugs until you symptoms decline and not engage with the hard work of psychological therapy.

Many doctors and patients like drug treatments for this reason.

Question 21

EVALUATION OF DRUG THERAPY

Outline the three limitations of drug therapy

Answer 21

• a limitation is that drugs can have side-effects
• a limitation is the evidence for drug treatment is unreliable
• one problem is that some cases of OCD follow trauma

Question 22

EVALUATION OF DRUG THERAPY

Explain the limitation of drug therapy in that it can have side-effects

Answer 22

Although drugs like SSRIs are often helpful, a significant minority will get no benefit. Some patients also suffer side-effects. For example some side-effects of SSRIs are indigestion,blurred vision and loss of sex drive.

For those taking Clomipramine, side-effects are more common and be more serious. More than 1 in 10 patients suffer erection problems and weight gain, 1 in 100 become aggressive and suffer disruption to blood pressure and heart rhythm.

Such factors reduce effectiveness because people stop taking the medication which is a weakness.

Question 23

EVALUATION OF DRUG THERAPY

Explain the limitation of drug therapy in that the evidence for drug treatment is unreliable

Answer 23

Although SSRIs are fairly effective and any side-effects will probably be short term, like all drug treatments, SSRIs have some controversy attached. For example, some believe that evidence favouring drug treatments is biased because it is sponsored by drug companies who do not report all evidence.

A weakness is that such companies may try to suppress evidence that does not support the effectiveness of their drugs to maximise their economic gain.

Question 24

EVALUATION OF DRUG THERAPY

Explain the limitation of drug therapy in that some cases of OCD follow trauma

Answer 24

OCD is widely believed to be biological in origin. It makes sense therefore that the standard treatment should be biological. However, it is acknowledged that OCD can have a range of other causes, and in that some cases it is a response to traumatic life events.

It may not be appropriate to use drugs when treating cases that follow a trauma when psychological therapies may provide the best option which is a weakness for drug treatment.

Question 25

What is the dis thesis-stress model?

Answer 25

It is an eclectic idea that suggests you need a genetic vulnerability and a stressful trigger.