The biological approach to treating OCD Flashcards
What does drug therapy mean?
Treatment involving drugs, i.e. chemicals that have a particular effect on the functioning of the brain or some other body system. In the case of psychological disorders such drugs usually affect neurotransmitter levels.
What is drug therapy?
Drug therapy for mental disorders aims to increase or decrease levels of neurotransmitters in the brain or to increase/decrease their activity. Low levels of serotonin are associated with OCD. Therefore drugs work in various ways to increase the level of serotonin in the brain .
What is SSRI’s?
The standard medical treatment used to tackle the symptoms of OCD involves a particular type of antidepressant drug called a selective serotonin reuptake inhibitor (SSRI).
SSRI 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 to the postsynaptic neuron and then it is reabsorbed by the presynaptic neuron where it is broken down and re-used.
By preventing the re-absorption and breakdown of serotonin
ssri’s effectively increase it’s levels in the synapse and thus continue to stimulate the postsynaptic neuron.
This compensate 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 this may be increase if it is not benefiting the patient.
the drug is also available as capsules or liquid
it takes 3 to 4 months of daily use for ssri’s to have much impact on symptoms
What does combining SSRIS with other treatment do?
Drugs are often used alongside cognitive behaviour therapy (CBT) to treat OCD. The drugs reduce a patients emotional symptoms, such as feeling anxious or depressed This means that patients can engage more effectively with CBT. In practice some people respond best to CBT alone whilst others benefit more form drugs like Fluoxetine. Occasionally other drugs are prescribed alongside SSRI.
What are alternatives to SSRIS?
When an SSRI is not effective after three to four months the dose can be increased (eg. up to 60mg a day for fluoxetine) or it can be combined with other drugs. Sometimes different anti-depressants are tried.
patients respond very differently to different drugs and alternative work well for some people and not at all for others
What is tricyclis as an alternative to SSRI?
(an older type of antidepressant) which are sometimes used, such as clomipramine. These have the same effect on the serotonin system as SSRI’S. clomipramine has more severe side-effects than ssri’s so it is generally kept in reserve for patients who do not respond to ssri’s
What is SNRI’s as an alternative to SSRI?
(serotonin noradrenaline reuptake inhibitors). in the last five years a different class of antidepressant drugs called snri’s has also been used to treat OCD. These are, like clomipramine, a second line of defence for patients who don’t respond to ssri’s. snri’s increase levels of serotonin as well as another different neurotransmitter - noradrenaline
Why is drug therapy is effective at tackling OCD symptoms a strength?
There is clear evidence for the effectiveness of SSRIs in reducing the severity of OCD symptoms and so improving quality of life OCD patients. Soomro et al (2009) reviewed studies comparing SSR I to placebos in the treatment of OCD and concluded that all 17 studies reviewed showed significantly better results for the SSR than for placebo conditions. Effectiveness is greatest when SSRI are combined with a psychological treatment, usually CBT. Typically symptoms declined significantly for around 70% of patients taking SSRI. Of the remaining 30% alternative drug treatments or combinations of drugs and psychological treatments will be effective for some. So drugs can help most patients with OCD.
Why is drugs being cost effective and non disruptive a strength?
An advantage of drug treatments in general is that they are cheap compare to psychological treatments. Using drugs to treat OCD is therefore good value for a public health system like the national health service. As compare to psychological therapy SSRI are also non-destructive to patients lives. If you wish you can simply take drugs until your symptoms decline and not engage with the hard work of psycho logical therapy. Many doctors and patients like drug treatments for these reasons.
Why is drugs having a side effect a limitation?
Although drugs like SSR I are often helpful to sufferers of OCD a significant minority will get no benefit. Some patients also suffer severe side-effects such as indigestion blurred vision and loss of sex drive. These side-effects are usually temporary.
For those taking Clomipramine side-effects are more common and can be more serious. More than one in 10 patients suffer erections problems tremors and weight gain. More than one in 100 become aggressive and severe disruption to blood pressure and heart rhythm . Such factors reduced effectiveness because people stop taking the medication.
