Antidepressants: SSRIs

Most commonly used drug for OCD are antidepressants
Low levels of neurotransmitter serotonin are associated with depression as well as OCD
- So drugs are used to increase levels
Low levels of serotonin are implicated in "worry circuit", so increasing levels of serotonin may therefore normalise this circuit
Antidepressants are used to reduce anxiety associated with OCD
- SSRIs - selective serotonin re-uptake inhibitors --> regulate mood and anxiety by increasing levels of serotonin
SSRIs:
- Serotonin is released into synapse from one nerve (neuron) --> targets receptor cells on receiving neuron at receptor sites
  - Afterwards, is re-absorbed by initial neuron sending message
- SSRIs inhibit this re-absorption in order to increase levels of serotonin at the synapse, and increase simulation to receiving neuron

Antidepressants: Tricyclics

Tricyclics are primarily used in treatment of OCD rather than depression
- They block transporter mechanism that re-absorbs serotonin and nor-adrenaline into pre-synaptic cell after it has fired
  - More of these neurotransmitters are left in synapse, prolonging their activity and easing transmission of next impulse
Advantage of targeting more than one neurotransmitter
- Greater side effects so are used as second-line treatment where SSRIs aren't effective

Anti-Anxiety Drugs

BZs are commonly used to reduce anxiety
- Slow down activity of neurotransmitter GABA (gamma-aminobutyric acid) --> when released has general quietening effect on many of neurons in brain
  - Reacts with special sites (GABA receptors) on outside of receiving neurons
  - When GABA locks onto these receptors, it opens channel that increases flow of chloride ions into neuron
    - Chloride ions make it harder for stimulation by neurotransmitters, thus slowing down activity and making person feel more relaxed

Other Drugs

Research has found that D-Cycloserine has effect on reducing anxiety and thus may be an effective treatment for OCD, particularly when used in conjunction with psychotherapy
- Antibiotic used in treatment of tuberculosis
- Appears to enhance transmission of GABA and thus reduce anxiety (Kushner et al 2007)

	Created by Niamh Webster over 7 years ago

A Level Psychology (Psychopathology) Note on Biological Approach to Treating OCD , created by Niamh Webster on 27/05/2019.