Obsessive-Compulsive and Related Disorders

Obsessive-Compulsive Disorder (OCD)

•    Definitions:

o    Obsessions: intrusive, unwanted, repetitive thoughts, images, or urges causing distress 

                                                                        (e.g., contamination, symmetry, harm)

o    Compulsions: repetitive behaviours or mental acts to reduce distress 

                                                                        (e.g., washing, checking, counting)

•    Clinical features:

o    Insight usually preserved, though can vary; poor insight = worse prognosis

o    Symptoms often ego-dystonic (experienced as alien to self)

•    Treatment:

o    First-line: CBT with exposure and response prevention (ERP)

o    SSRIs (e.g., fluoxetine, sertraline) at higher doses, and longer treatment trial (≥12 weeks before judging efficacy)

o    Clomipramine (TCA) sometimes used if SSRI-resistant

o    Severe cases: consider augmenting with antipsychotics (e.g., risperidone)

•    Pearls:

o    Check for comorbid depression (common)

o    Avoid benzodiazepines; may worsen long-term course


Body Dysmorphic Disorder (BDD)

•    Features:

o    Preoccupation with perceived defect or flaw in appearance (often minimal or not observable to others)

o    Repetitive behaviours: mirror checking, excessive grooming, reassurance seeking

o    Commonly affects face, skin, hair

•    Impact:

o    Significant distress or impairment in social, occupational, or other areas

o    High rates of comorbid depression, suicidal ideation

•    Treatment:

o    CBT focusing on cognitive restructuring and exposure

o    SSRIs helpful, often at higher doses


Trichotillomania (Hair-Pulling Disorder)

•    Features:

o    Recurrent pulling out of hair (scalp, eyebrows, eyelashes) noticeable hair loss

o    Repeated attempts to stop

o    Can be accompanied by tension before pulling and relief after

•    Treatment:

o    CBT (habit reversal training)

o    SSRIs have variable benefit


Hoarding Disorder

•    Features:

o    Persistent difficulty discarding possessions regardless of value

o    Perceived need to save items; distress with discarding

o    Results in clutter, impairing living spaces and function

•    Treatment:

o    CBT focused on hoarding

o    SSRIs less consistently effective compared to classic OCD



Extra Revision Pearls

•    OCD may present in children; consider PANDAS 

                    (Paediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections) if sudden onset.

•    In OCD, compulsions are usually performed to prevent feared event, not for pleasure.

•    BDD patients often seek dermatological or surgical interventions poor outcomes without psychological treatment.

•    Trichotillomania and hoarding now classified under OCD-related disorders in DSM-5.

•    Insight varies: poor insight worse prognosis and poorer treatment response.