3.9. OCD Treatment: Biological Approach Flashcards
What is the most commonly used biological therapy for anxiety disorders?
Drug therapy
What does drug therapy assume?
There is a chemical imbalance in the brain.
What can chemical imbalances be corrected by?
Drugs
What do drugs do?
Either increase or decrease the levels of neurotransmitters in the brain.
Antidepressants: SSRIs
- Drugs to increase serotonin are used with mental disorders
- Low levels of serotonin are involved in the worry circuit, so increasing levels can normalise this and so aid anxiety levels.
- SSRIs are the preferred drug, they increase levels of serotonin which regulates mood and anxiety.
- As a result, more serotonin is available in the synapse for longer, so the activity is prolonged and this helps the neurons to communicate.
What are antidepressants used to do?
Reduce the anxiety associated with OCD
How does serotonin work?
- Release into synapse from one nerve.
- Targets receptor cells on the receiving neuron at receptor sites.
- Afterwards, it is reabsorbed by the initial neuron sending the message.
- In order to increase levels of serotonin at the synapse, and increase stimulation to the receiving neuron, this reabsorption is inhibited
Fluoxetine (an SSRI):
- Typical daily dose of 20mg (but can be increased to 60mg a day if needed)
How long does it take SSRIs to work?
Takes 3-4 months of daily use for SSRIs to impact on symptoms
Antidepressants: tricyclics
- Clomipramine is primarily used in the treatment of OCD, not depression
- Tricyclics block the mechanism that reabsorbs both serotonin and noradrenaline, prolonging their activity.
What do tricyclics have the advantage of doing?
Targeting more than one neurotransmitter
Problem of tricyclics
They have greater side effects
Anti-anxiety: Benzodiazepines
- Commonly used to reduce anxiety
-Bzs slow down the activity of the central nervous system by enhancing the activity of the neurotransmitter GABA (neurotransmitter that has a calming influence on the brain) - This is the neurotransmitter that has a general quieting effect on many of the neurons in the brain.
- Bzs bind to the GABA receptors on the post-synaptic neuron, allowing chloride ions to flow
Other drugs:
- Research has shown that D-cycloserine has an effect on reducing anxiety, thus may be an effective treatment for OCD, particularly when used in conjunction with psychotherapy
What is drug treatment better combined with?
Any other treatment
What do drugs reduce?
Anxiety and get rid of depression, allowing the person to live a normal life (while on drugs)
As they suppress the symptoms, drugs give them the motivation to go and seek help to change the obsessions and the compulsions.
Otherwise they will have to remain on drugs for the rest of their lives.
Strength: effectiveness
- Soomro reviewed 17 studies of the use of SSRIs with OCD patients and found them to be more effective than placebos in reducing symptoms of OCD for up to 3 months after treatment -> only short term
- However, most studies are only 3-4 months long, therefore little long term data actually exists
Strength: drug therapies are preferred to other methods
- Drug therapy generally requires less time and effort than therapies such as CBT, therefore it’s quick and people only have to take a pill rather than sit through 20 1 hr sessions with a therapist
- It’s relatively cheap and requires less monitoring
- Some benefits may derive from simply talking to the doctor during consultations (dodo bird effect)
Weakness: side effects
- SSRI side effects are nausea, headaches, insomnia
- Bz side effects include increased aggression, long term impairments of memory and possible addiction
- Side effects may amount to costs that more than outweigh the benefits and stop a patient taking the drug
Weakness: not a lasting cure
- Koran suggested that although drug therapy may be more commonly used, psychotherapy such as CBT should be tried first
- Drug therapy must be efficient in the short term but it doesn’t provide a lasting cure.
- A lot of patients relapse within a few weeks if medication is stopped.
