5.10 OCD: biological treatment

Biological Treatment of OCD

Focuses mainly on *drug therapy**.

Based on the idea that OCD is linked to *abnormal neurotransmitter levels**, especially low serotonin.

Drug Therapy

Aim

* To increase or decrease neurotransmitters in the brain to improve functioning.

In OCD, treatment usually aims to *increase serotonin levels**.

SSRIs (Selective Serotonin Reuptake Inhibitors)

A type of *antidepressant** commonly used to treat OCD.

* Examples:

* Fluoxetine (Prozac)

* Sertraline

* Paroxetine

How SSRIs Work

Neurons communicate through the *synapse** using serotonin.

Normally, serotonin released into the synapse is later *reabsorbed** (reuptake).

SSRIs *block reuptake**, leaving more serotonin in the synapse.

* This increases stimulation of the postsynaptic neuron and improves mood/OCD symptoms.

Dosage

* Usually taken daily.

Often takes *3–4 months** before symptoms improve noticeably.

* Dose may be increased if symptoms persist.

Combining SSRIs with Other Treatments

CBT + SSRIs

SSRIs are often used alongside *Cognitive Behaviour Therapy (CBT)**.

* Drugs reduce emotional symptoms so patients can engage more effectively in CBT.

* Combination therapy is often more effective than drugs alone.

Alternatives to SSRIs

Tricyclics

Example: *Clomipramine**

* Older antidepressant that affects serotonin.

* Usually prescribed when SSRIs fail.

* More side effects than SSRIs.

SNRIs

Example: *SNRIs (Serotonin-Noradrenaline Reuptake Inhibitors)**

* Increase both serotonin and noradrenaline.

* Used if SSRIs are ineffective.

Evaluation

Effective Treatment

* Research shows SSRIs reduce OCD symptoms for many patients.

* Drugs are generally more effective than placebos.

Around *70%** of patients improve with SSRIs.

Cost-Effective and Convenient

* Cheaper than psychological therapies.

* Easy to administer.

* Requires less therapist time.

* Useful for severe OCD symptoms.

Side Effects

* Some patients experience: Nausea, Insomnia, Headaches, Loss of sex drive

* Clomipramine may cause: Weight gain, Aggression

* Side effects can reduce quality of life and stop people taking medication.

Not Effective for Everyone

* Some patients do not respond to drugs.

* Psychological therapies may still be required.

Biased Evidence

* Drug research is often funded by pharmaceutical companies.

* Positive results may be more likely to be published.

Example Study

## Soomro et al. (2009)

* Reviewed studies comparing SSRIs with placebos.

* Found SSRIs significantly reduced OCD symptoms.

Key Terms

## Drug Therapy

* Treatment involving chemicals that affect the brain or nervous system.

## Neurotransmitter

* Chemical messenger that transmits signals between neurons.

## Serotonin

* Neurotransmitter linked to mood and OCD symptoms.

## Synapse

* Gap between neurons where neurotransmitters pass messages.