Biological approach in treating OCD

Aim of biological approach to treat OCD

• regulate levels of neurotransmitters in the brain.

• does this by using anti- depressants (SSRIs) and anti- anxiety drugs (Benzodiazepine)

Benzodiazepine in treating OCD

• increases the effect of the neurotransmitter GABA

• GABA has ‘quietening effect’- inhibits neurons- makes them less likely to fire, tells neurone to stop stressing

• GABA locks onto receptor site, increasing flow of chlorine ions into neuron.

• Chlorine ions make it harder for neuron to be stimulated by other NT’s so slows nervous system- patient more relaxed.

• when BZD binds to receptor sites- increases effects of gaba

• So anxiety (caused due to obsessive thoughts, compulsions) is reduced - improving OCD symptoms

Strength- Research support for SSRIs

• Randomised drug trails compared effectiveness of SSRIs and placebo drug

• Soomro et al did research about this- found SSRIs were more effective than placebo treating OCD across 17 trials

• Supports biological treatment. But studies critised only looking at short term effectivness of drugs not LT

Weakness- Symptoms not the cause

• Drugs only treat symptoms of disorder not cause

• SSRIs increase levels of serotonin in bran reducing anxiety, relives symptoms of OCD- dosent treat cause.

• Once patient stops taking drug, prone to relapse.

• Koran et al suggest psychological treatment like CBT more effective LT solution- lasting treatment.

Strength- Preferable to other treatments

• little input from user- less motivation, time needed.- Cost effective

• Contrast- therapies like CBT need patient attending regular meetings, high motivation.

• Drug therapies cheaper for health services as need little monitoring, cost less than psychological treatments- doctors prefer.

• Means drug therapies are more economical for health services, more attractive to patients than psychological treatments.

Weakness- Side effects

• SSRIs cause nausea, headaches and Benzodiazepine increases aggressiveness, LT mem impairment.

• Addiction problems in BNZO so limited to max of 4 weeks.

• So side effects aren’t severe but may cause patient to not want to take them. Limits effectiveness of drug treatments.

SSRIs in treating OCD

Low levels of serotonins associated with OCD due to less serotonin being produced or serotonin being re absorbed

• SSRIs increase serotonin by preventing reuptake in presynaptic neurone- increases serotonin levels in synapse

• Results in more serotonin received by the postsynaptic neuron (more in synapse)

• So correct info about persons mood is transmitted - reduces OCD symptoms

Alternative antidepressant- Tricyclics

If after 3-4months SSRIs aren’t effective, can use other drugs.

• TCYS block transporter mechanism that re-absorbs serotonin and noradrenaline.

• So more of these NTs left in synapse, prolonging their activity

• Target more than one NTs but have greater side effects so used as treatment if SSRIs weren’t effective.

Alternative antidepressant- SNRIs (serotonin-noradrenaline reuptake inhibitors)

• Increase levels of serotonin and noradrenaline

• Used when patients don’t respond to SSRIs