The Biological Approach to Treating OCD Flashcards
What is the most common form of treatment for OCD
Drug Treatment
What drugs are often used to treat OCD
Antidepressants like SSRI’s or tricyclics, as well as anti-anxiety drugs like Benzodiazepines and D-Cycloserine
How do Selective Serotonin Re-uptake Inhibitors help deal with OCD
Low levels of serotonin are associated with depression as well as OCD, particularly in the worry circuit which may be normalised with more serotonin.
What do SSRI’s do
SSRI’s increase serotonin levels by targeting receptor cells on the recieving neuron at receptor sites and afterwards are re-absorbed into the intial neuron, and inhibit the reuptake of serotonin to increase the amount of levels of serotonin at the synapse
How do tricyclics increase serotonin levels
They block the transporter mechanism that re-absorbs both serotonin and noradrenaline into the pre-synaptic cell after it has fired. As a result, more of these neurotransmitters are left in the synapse, proloning activity and easing transmission of the next impulse
What is an advantage of tricyclics over SSRI’s
They target more than one neurotransmitter, however they also have greater side effects so are used as a second choice treatment
What anti-anxiety drugs can be used to treat OCD
Bezodiazepines and D-Cycloserine
Why do Benzodiazepines help treat OCD
They enhance the activity of the neurotransmitter GABA, which has a general quieting effect on many neurons in the brain when released.
How do Benzodiazepines work
It reacts with GABA receptors on the outside of receiving neurons. When GABA locks on to these receptors it opens up a channel that increases the flow of chloride ions into the neuron. Chloride ions make it harder for the neuron to be stimulated by other neurotransmitters, thus slowing down it’s activity and making the person feel more relaxed.
Why might D-Cycloserine’s help treat OCD
More recent research has found that D-Cycloserine has an effect on reducing anxiety and thus may be an effective treatment for OCD, as it also seems to enhance the transmission of GABA.
What is some evidence of the effectiveness of drug treatments for OCD
Soomro et al reviewed 17 studies of the use of SSRI’s with OCD patients and found them to be more effective than placebos in reducing OCD symptoms up to three months after treatment. However most studies are limited to only 3 - 4 months duration.
How are side effects a major drawback for drug treatments of OCD
Nausea, headaches and insomnia are all common side effects of SSRI’s and these are often enough to stop a patient taking the drug. Tricyclic’s tend to have more severe side effects, such as hallucination and irregular heartbeats, so are only used in cases where SSRI’s are ineffective. Benzodiazepines can cause increased aggressiveness and long-term impairment of memory. They also have issues with addiction, so they should be limited to four weeks.
What are the side effects of SSRI’s
Nausia, headaches and insomnia
What are the side effects of Tricyclics
halluciantion and irregular heartbeats
What are the side effects of Benzodiazepines
Increased Aggressiveness and long term impairment of memories
Who reviewed studies of the effectiveness of drug treatments for OCD
Soomro
Who found that positive drug studies get published and naughty ones get punished
Turner et al
Who found that patients relapse within a few weeks if medication stopped
Maina
Who suggested that psychotherapies for OCD should be used before drugs
Koran et al
