Treating OCD

Question 1

Drug Therapy

Answer 1

Biological treatments for OCD aim to restore biological imbalances, such as too little serotonin.

Drug treatments are based on the assumption that chemical imbalances are the main cause of the problem.

Two types of drug are used for the treatment of OCD:
1) Anti-depressants
2) Anti-anxiety drugs

Question 2

1) Anti-depressants (SSRIs)

Answer 2

• The biological explanation suggests that OCD (and depression) is the result of low levels of serotonin in the brain.
• SSRIs (selective serotonin re-uptake inhibitors) are one type of anti-depressant drug, which include drugs like Prozac.
• When serotonin is released from the pre-synaptic neuron into the synapse, it travels to the receptor sites on the post-synaptic neuron. Serotonin which is not absorbed into the post-synaptic neuron is reabsorbed into the pre-synaptic neuron. SSRIs increase the level of serotonin available in the synapse by preventing it from being reabsorbed into the pre-synaptic neuron. This increases the level of serotonin in the synapse and results in more serotonin being received by the post-synaptic neuron.
• Anti-depressants (like anti-anxiety drugs) improve mood and reduce anxiety which is experienced by patients with OCD.

Question 3

2) Anti-anxiety drugs

Answer 3

• Benzodiazepines (BZs) are a range of anti-anxiety drugs, which include trade names like Valium and Diazepam.
• BZs work by enhancing the action of the neurotransmitter GABA (gamma-aminobutyric acid) which is an inhibitory neurotransmitter.
• GABA tells neurons in the brain to ‘slow down’ and ‘stop firing’ and around 40% of the neurons in the brain respond to GABA.
• This means that BZs have a general quietening effect on the brain and consequently reduce anxiety, which is experienced as a result of the obsessive thoughts.

Question 4

SSRIs

Answer 4

• Selective Serotonin Reuptake Inhibitor
• SSRIs prevent reabsorption and breakdown of serotonin - increases level in the synapse and stimulates post-synaptic neurons.
• Dosage varies.
• Daily dose of Fluoxetine is 20mg but takes 3-4 months to have an impact.

Question 5

Tricyclics

Answer 5

• For example, clomipramine.
• Have the same effect on the serotonin system as SSRIs.
• Clomipramine has more side-effects than SSRIs so it is generally kept in reserve for patients who do not respond to SSRIs.

Question 6

SNRIs

Answer 6

• These are, like clomipramine, a 2nd line of defence for patients who don’t respond to SSRIs.
• They increase levels of serotonin as well as another neurotransmitter - noradrenaline.

Question 7

Strength

Answer 7

One strength of drug treatment for OCD is good evidence for its effectiveness. There is clear evidence to show that SSRIs reduce symptom severity and improve the quality of life for people with OCD. For example, G. Mustafa Soomro et al. (2009) reviewed 17 studies that compared SSRIs to placebos in the treatment of OCD. All 17 studies showed significantly better outcomes for SSRIs than for the placebo conditions. Typically symptoms reduce for around 70% of people taking SSRIs. For the remaining 30%, most can be helped by either alternative drugs or combinations of drugs and psychological therapies. This means that drugs appear to be helpful for most people with OCD.

Counterpoint: There is some evidence to suggest that even if drug treatments are helpful for most people with OCD, they may not be the most effective treatments available. Petros Skapinakis et al. (2016) carried out a systematic review of outcome studies and concluded that both cognitive and behavioural (exposure) therapies were more effective than SSRIs in the treatment of OCD. This means that drugs may not be the optimum treatment for OCD.

Question 8

Strength

Answer 8

One further strength of drugs is that they are cost-effective and non-disruptive to people’s lives. A strength of drug treatments for psychological disorders in general is that they 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. As compared to psychological therapies, SSRIs are also non-disruptive to people’s lives. If you wish, you can simply take drugs until your symptoms decline. This is quite different from psychological therapy which involves time spent attending therapy sessions. This means that drugs are popular with many people with OCD and their doctors.

Question 9

Weakness

Answer 9

One limitation of drug treatments for OCD is that drugs can have potentially 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. For those taking the tricyclic clomipramine, side-effects are more common and can be more serious. For example more than 1 in 10 people experience erection problems and weight gain, 1 in 100 become aggressive and experience heart-related problems. 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.