biological treatment for OCD

what is the most commonly use biological therapy?

drug therapy

what does drug therapy assume?

chemical imbalance in the brain

what do drugs do?

increase/decrease levels of neurotransmitters

what does SSRI stand for?

selective serotonin reuptake inhibitors

what do SSRIs do?

increase certain transmitters in the brain by preventing the reabsorption of serotonin

what do SSRIs allow?

the effective increase of serotonin the synapse that can stimulate the postsynaptic neuron

what is often used alongside drugs?

CBT

why are CBT & drugs combined?

drugs reduce emotional symptoms so patient can engage more effectively with the therapy

what are the alternatives to SSRIs?

• tricyclics

• benzoiazepines

why are alternatives to SSRIs used?

when SSRIs are not effective after 3-4 months

what is a tricyclic?

the first antidepressant for OCD

what does a tricyclic do?

blocks the transporter mechanism that reabsorbs both serotonin & noradrenaline into the presynaptic neuron after it has been fired which prolongs the activity as they are left in the synapse

what is the advantage of using tricyclics?

they target more than one neutransmitter

what is the drawback of tricyclics?

greater side effects than SSRIs

what are benzodiazepines?

anti-anxiety drugs

how do BZs work?

slow down the activity of the CNS by enhancing the activity of GABA

what does GABA stand for?

gamma-aminobutyric acid

what is GABA?

a neurotransmitter that when released has a quieting effect on many of the neurons in the brain by reacting with GABA receptors on the outside of the receiving neurons

what does a GABA do?

locks into the GABA receptors, opening a channel that increases the flow of chloride ions into the neuron

why should the flow of chloride ions into the neuron be increased?

they make it harder for the neuron to be stimulated by other neurotransmitters, slowing down activity & making them more relaxed

what are the strengths of the biological treatment of OCD?

• evidence - effectiveness tested in studies - compared to placebo - Soomro et al - 17 studies reviewed - SSRIs more effective than placebo - up to 3 months after treatment - only looks at short term

• cost-effective - non-disruptive - little monitoring - unlike psychotherapy, no effort/time - favourable - economic

what are the weaknesses of the biological treatment of OCD?

• side effects - significant minority - weight gain - nausea - headaches - tricyclics have more - withdrawal - relapse

• unreliable evidence - drug companies sponsorship - publication bias - Turner - 31% of studies for antidepressants registered & reported to FDA were never published - inappropriate treatment decisions