DRUG THERAPY
– Drug therapy for disorders aims to increase or decrease levels of neurotransmitters in the brain or to increase/decreases their activity.
SSRIs
– The standard medical treatment used to tackle the symptoms of OCD involves a particular type of antidepressant drug called a selective serotonin reuptake inhibitor.
– SSRIs work on the serotonin system in the brain.
– Serotonin is released by certain neurons in the brain.
– 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 re-used.
– By preventing the re-absorption and breakdown of serotonin SSRIs effectively increase its levels in the synapse and thus continue to stimulate the postsynaptic neuron.
– This compensates for whatever is wrong with the serotonin system in OCD.
– Dosage and other advice vary according to which SSRI is prescribed.
– A typical daily dose of Fluoxetine is 20mg although they may be increases if it is not benefiting the patient. – The drug is available as capsules or liquid.
– It takes three to four months of daily use of SSRIs to have much impact on symptoms.
COMBINING SSRIs WITH OTHER TREATMENTS
– Drugs are also used alongside CBT to treat OCD.
– The drugs reduce a patient’s emotional symptoms, such as feeling anxious or depressed.
– This means that patients can engage more effectively with the CBT.
ALTERNATIVES TO SSRIs
– Where an SSRI is not effective after three to four months the dose can be increased or it can be combined with other drugs.
– Alternatives work well for some people and not at all for others.
TRICYCLICS
– Are sometimes used, such as Clomipramine.
– These have the same effect on the serotonin as SSRIs but more severe side-effects and so are kept in reserve for patients do not respond to SSRIs.
SNRIs
– These are serotonin-noradrenaline reuptake inhibitors.
– These are a second line of defence for patients who don’t respond to SSRIs and they increase the levels of serotonin as well as another different neurotransmitter – noradrenaline.
EVALUATION OF DRUG THERAPIES
STRENGTHS
Low Cost
– An advantage of drug treatments in general is that they are cheap compared to psychological treatments. – Using drugs to treat OCD is therefore good value for a public health system like the NHS.
– As compared to psychological therapies SSRIs are also non-disruptive to patients’ lives.
– Drugs can have side-effects. For example, some patients suffer from indigestion, blurred vision and loss of sex drive.
– These side effects are usually temporary.
– Such factors reduce effectiveness because people stop taking the medication.
Effectiveness
– There is evidence towards the effectiveness of drug therapies
– A randomised control trial is used to compare the effectiveness of the drug versus a placebo
– Soomro et al reviewed 17 studies of the use of SSRIs with OCD patients and found them to be more effective than placebos in reducing the symptoms of OCD
– However, there is a lack of long term data
LIMITATIONS
Other Factors
– OCD is widely believed to be biological 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 that in some cases it is a response to a traumatic life event.
– This may mean that drugs are not the appropriate form of treatment for this type of OCD.
Side Effects
– Neusa, headaches and insomnia are common side effects of SSRIs
– Although not always server, they are often enough to mean the patient stops taking the drug
– Tricyclic antidepressants tend to have more side effects than SSRIs and are only used when SSRIs are not effective
– The possible side effects of BZs include increased aggressiveness and long term impairment of memory
– There are also problems with addiction, so the recommendation is that BZ use should be limited to a maximum of 4 weeks
– These side effects, and the possibility of addiction, therefore limit the usefulness of drugs as treatments