Condition

Obsessive-Compulsive Disorder (OCD)

Editors: Adrian Preda MD; Esther Jolanda van Zuuren MD; Alexander Rae-Grant MD, FRCPC, FAAN

Overview and Recommendations
Background Information
History and Physical
Diagnosis
Management
Complications
Prognosis
Prevention and Screening
Guidelines and Resources
Patient Information
References

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Background Information

Description

Obsessive-compulsive disorder (OCD)is a neuropsychiatric disorder characterized by obsessions and/or compulsions that are distressing, time-consuming, or cause substantial impairment.^1
,2
,3
,5
OCD was previously classified as an anxiety disorder, but the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) designates OCD as the lead disorder in a cluster of related disorders including body dysmorphic disorder, hoarding disorder, trichotillomania, and excoriation disorder (Impact of the DSM-IV to DSM-5 Changes on the National Survey on Drug Use and Health. Substance Abuse and Mental Health Services Administration 2016 PDF).

Definitions

Obsession - Repetitive or persistent thoughts that are intrusive, unwanted, and cause distress or anxiety.^1
,2
,5
Compulsions (also called rituals) - Repetitive behaviors or mental acts that are not intrinsically pleasurable and are performed in response to an obsession.^1
,2
,5
Ruminations - Repetitive mental acts performed in response to intrusive thoughts.²
Delusions - Obsessions without preserved insight.³

Image 1 of 1

Common compulsions in obsessive-compulsive disorder

Mental acts such as checking one's memory, asking for forgiveness, excessive praying, or avoiding triggers; repetitive checking or seeking assurance from others; reordering objects or repeating actions multiple times; repetitive washing, cleaning.

Types

The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) identifies OCD specifiers.^1
,5
- Level of insight specifier:
  - Good or fair insight refers to a recognition that one's OCD beliefs are definitely or probably not true.
  - Poor insight refers to the conviction that one's OCD beliefs and/or behaviors are not problematic despite contrary evidence.
  - Absent insight/delusional beliefs refers to the conviction that one's OCD beliefs are true, which is associated with poorer outcome.
- Presence of tics specifier; patient may have a tic disorder or a family history of tic disorder
See Clinical presentation for common patterns of obsessions and/or compulsions.

Epidemiology

Incidence/Prevalence

The age of onset of OCD is typically bimodal and begins prior to age 30.¹
- Mean age of onset is 10 years old in children.
- Another peak of new-onset cases occurs in adolescence and young adulthood, where the mean age of onset is 19-21 years.
There is a reported 1%-3% lifetime prevalence in adults and an estimated 1%-2% prevalence in children (^1
,2
,5, J Am Acad Child Adolesc Psychiatry 2012 Jan;51(1):98)
OCD appears to occur more frequently in male children, but there appear to be no sex differences in the incidence of OCD by adulthood.¹
STUDY SUMMARY
cumulative incidence 0.4% of OCD cases at age 23 years in Finland
COHORT STUDY: BMC Psychiatry 2017 Feb 10;17(1):64
based on population-based national cohort study

1,390,172 live births from national registry in Finland between 1987 and 2009 were evaluated for incidence of OCD

cases of OCD defined as individuals diagnosed with OCD and registered by end of 2012

3,372 cases of OCD; 1,579 (47%) male persons and 1,793 (53%) female persons

cumulative incidence of OCD cases 0.4% by age 23 in all children born in 1987-1989

mean age at OCD diagnosis 15.2 years (range 3-25 years)

cumulative incidence of OCD cases by age 15 years per 10,000 live births
born in 1987-1989
12.4 in male children

8.5 in female children

born in 1993-1995
23.7 in male children

28 in female children

70.8% of male persons and 74.8% of female persons diagnosed with ≥ 1 comorbid psychiatric or neurodevelopmental disorder, most commonly
anxiety disorders (32.8% in male persons, 46.5% in female persons)

depressive disorders (29.8% in male persons, 46.3% in female persons)

psychotic disorders (15.3% in male persons, 11.3% in female persons)

Reference - BMC Psychiatry 2017 Feb 10;17(1):64

Risk Factors

Risk factors for OCD include:
- Family history of OCD,
  - Estimated heritability is reported to range from 27%-65%.¹
    - Childhood-onset OCD heritability: 45%-65%.
    - Adolescent- or adult-onset OCD heritability: 27%-47%.
  - Monozygotic twins have been reported to have a higher concordance rate for OCD (0.52) than dizygotic twins (0.21), with an overall estimated heritability for OCD reported to be 48% in this population (JAMA Psychiatry 2014 Feb;71(2):182, Psychiatr Clin North Am 2014 Sep;37(3):319 full-text).
- Exposure to childhood adversity such as abuse, neglect, social isolation, or bullying²
- Presence of internalizing symptoms and higher degree of negative emotionality (Psychol Med 2011 Dec;41(12):2495)
- History of anxiety sensitivity (J Child Psychol Psychiatry 2020 Sep;61(9):979)
- Perinatal and pregnancy-related factors, including illness requiring medical care during pregnancy and birthing difficulties (J Child Adolesc Psychopharmacol 2008 Aug;18(4):373)
Factors including parental age, season of birth, socioeconomic status, parental rearing practices, infections, traumatic brain injury, substance use, or vitamin deficiency have not been found to increase risk of OCD (Neurosci Biobehav Rev 2016 Jun;65:36).
STUDY SUMMARY
stressful life events may be associated with increased obsessive-compulsive symptoms in adolescence
COHORT STUDY: Eur Psychiatry 2019 Feb;56:35
based on prospective cohort study

2,616 participants at time 1 (mean age 15 years) and 1,579 participants at time 2 (mean age 17 years) completed self-report questionnaires 2 years apart assessing obsessive-compulsive symptoms, maternal and paternal punitive parenting, and dependent stressful life events
time 1 included 689 monozygotic (MZ) twins, 1,267 dizygotic (DZ) twins, 576 full siblings (FS), and 84 unknown participants

time 2 included 439 MZ twins, 816 DZ twins, 299 FS and 25 unknown participants

obsessive-compulsive symptoms measured by self-reported, 6-item obsessive-compulsive symptom subscale of Spence Children’s Anxiety Scale (scored on 4-point scale, with total score between 0 and 18)

parental punitive discipline assessed by adolescent-report, 5-item measure of negative sanctions (scored on 5-point scale, with total score between 0 and 20)

dependent stressful life events assessed by Life Event Scale for Adolescents, with total score representing total number events reported

stressful life events associated with increased obsessive-compulsive symptoms in adolescence (p < 0.001)

no significant association between maternal or paternal punitive discipline and increased obsessive-compulsive symptoms

Reference - Eur Psychiatry 2019 Feb;56:35
STUDY SUMMARY
COVID-19 associated with increased risk of anxiety and other psychiatric illness within 90 days in United States
COHORT STUDY: Lancet Psychiatry 2020 Nov 9 early online
Psychiatric_DisordersCOVID-19 associated with increased risk of anxiety and other psychiatric illness within 90 days in United States (Lancet Psychiatry 2020 Nov 9)11/14/2020 12:50:29 PM
based on population-based cohort study

62,345 patients aged ≥ 10 years (mean age 49 years, 55% female, 51% White) with COVID-19 in United States were compared to propensity score-matched patients with other health events for incident psychiatric diagnosis 14-90 days after health event
other health events included influenza (26,497 patients), other respiratory tract infection (44,775), skin infection (38,977), cholelithiasis (19,733), urolithiasis (28,827), and large bone fracture (37,841)

patients excluded if health event before January 20, 2020 or if they died or had health event after August 1, 2020

propensity scores based on baseline characteristics including risk factors for COVID-19 and severe COVID-19

COVID-19 associated with increased risks of
first psychiatric illness
5.8% with COVID-19 (p < 0.0001 vs. each of the other health events)

2.5%-3.4% with other health events

consistent results in most sensitivity analyses such as those based on race, housing and economic factors, and laboratory confirmed COVID-19

increased risk compared to most other health events also for anxiety disorders, mood disorders, insomnia, and dementia (in patients aged ≥ 65 years)

any incident psychiatric illness (including first diagnosis and relapse)
18.1% with COVID-19 (p < 0.0001 vs. each of the other health events)

12.7%-15.1% with other health events

increased risk compared to most other health events also for anxiety disorders, mood disorders, and psychotic disorders

Reference - Lancet Psychiatry 2020 Nov 9 early online, correction can be found in Lancet Psychiatry 2020 Nov 12 early online
STUDY SUMMARY
perinatal factors may be associated with increased risk for OCD in offspring
COHORT STUDY: JAMA Psychiatry 2016 Nov 1;73(11):1135
based on population-based cohort study

2,421,284 children from singleton births in Sweden from January 1, 1973 to December 31, 1996 who were followed through December 31, 2013 were included

out of 1,403,651 families in cohort, differentially exposed siblings from 743,885 families with siblings were evaluated, and of these, 11,592 families included full siblings that were discordant for OCD

17,305 persons out of 2,421,284 cohort individuals diagnosed with OCD (0.71%)

mean age at first diagnosis 23years

perinatal factors associated with increased OCD in offspring
smoking ≥ 10 cigarettes/day during pregnancy (hazard ratio [HR] 1.27, 95% CI 1.02-1.58)

breech presentation (HR 1.35, 95% CI 1.06-1.71)

delivery by cesarean section (HR 1.17, 95% CI 1.01-1.34)

preterm birth (HR 1.24, 95% CI 1.07-1.43)

birth weight 1,501-2,500 grams (HR 1.3, 95% CI 1.05-1.62) and 2,501-3,500 grams (HR 1.08, 95% CI 1.01-1.16)

being large for gestational age (HR 1.23, 95% CI 1.05-1.45)

Apgar distress scores at 5 minutes (HR 1.5, 95% CI 1.07-2.09)

Reference - JAMA Psychiatry 2016 Nov 1;73(11):1135

Associated Conditions

OCD is associated with other psychiatric disorders, especially anxiety disorders and mood disorders. In fact, about 90% of persons with OCD meet criteria for ≥ 1 other psychiatric disorder.^2
,5
- Anxiety and trauma-related disorders have been reported in about 76% persons with OCD overall, including
  - Social anxiety disorder in 33%-44%
  - Specific phobia in 25%-43%
  - Panic disorder in 20%
  - Posttraumatic stress disorder in 19%
  - Generalized anxiety disorder in 8%-10%
- Any mood disorder has been reported in about 63% of persons with OCD, including
  - Major depressive disorder in about 41%
  - Bipolar disorder in about 23%
- Impulse control or neurodevelopmental disorders have been reported in about 56% of persons with OCD, including
  - Any tic disorder in about 30%, with Tourette syndrome reported in about 20%
  - Oppositional defiant disorder Oppositional Defiant Disorder in about 28%
  - Attention Deficit Hyperactivity Disorder (ADHD) in about 19%
  - Intermittent explosive disorder in about 19%
  - Conduct disorder in about 14%
- Other obsessive-compulsive and related disorders, including
  - Body dysmorphic disorder
  - Trichotillomania (hair-pulling disorder)
  - Hoarding disorder, which appears to be associated with early age at onset and more severe disease in children and adolescents with OCD
  - Excoriation (Skin-picking) disorder
- Substance use disorders have been reported in about 39%, including alcohol use disorder in about 25%.
- See Mol Psychiatry 2010 Jan;15(1):53 full-text for historical epidemiological data.
Other psychiatric comorbidities associated with OCD include:^2
,5
- Schizophrenia or schizoaffective disorder; OCD diagnosed in about 10%-12% of persons with either of these disorders
- Eating disorders, such as anorexia nervosa and bulimia nervosa; OCD diagnosed in about 20% of persons with either of these disorders
In children and adolescents with OCD, psychiatric comorbidities have been reported in up to 50% of patients. Younger age at OCD onset is associated with an increased risk for an of the following:^2
,5
- Attention-deficit hyperactivity disorder (ADHD)
- Specific phobias, including agoraphobia
- Anxiety disorders, including separation anxiety
- Tourette syndrome
- Pediatric acute-onset neuropsychiatric syndrome (PANS), which is presumed to be an autoimmune encephalopathy of childhood
  - PANS is characterized by the abrupt onset of OCD or severe food/fluid intake restriction, as well as ≥ 2 additional neuropsychiatric symptoms.
  - A subset of PANS, pediatric autoimmune neuropsychiatric disorder associated with group A streptococcal infections (PANDAS), is characterized by OCD and/or tic disorder, and a temporal relationship between symptoms and group A streptococcal (GAS) infection.
STUDY SUMMARY
hoarding compulsions appear associated with higher levels of impairment, and slightly higher prevalence of certain tic and anxiety disorders in children with OCD
CASE-CONTROL STUDY: J Obsessive Compuls Relat Disord 2014 Oct 1;3(4):325
based on case-control study

163 children (age range 6-17 years; 58% aged 9-14 years) with OCD and hoarding compulsions and 478 children with OCD without hoarding had symptom severity, comorbidities, and overall impairment compared

comparing children with hoarding vs. those without
significant or extreme impairment 44% vs. 31% (p < 0.01)

panic disorder diagnosis in 8% vs. 3% (p = 0.03)

Tourette syndrome in 7% vs. 3% (p < 0.01)

tics in 36% vs. 28% (p = 0.07)

mean age of OCD onset 6 years vs. 7 years (p < 0.001)

Reference - J Obsessive Compuls Relat Disord 2014 Oct 1;3(4):325
STUDY SUMMARY
hoarding symptoms appear associated with earlier age at diagnosis and higher rate of comorbid ADHD and anxiety disorders in children with OCD
CASE-CONTROL STUDY: J Obsessive Compuls Relat Disord 2014 Jan 1;3(1):6
based on case-control study

33 children aged < 10 years (mean age 7 years) with OCD plus hoarding behavior and 35 children with OCD without hoarding symptoms were evaluated

hoarding symptoms determined with clinician rating on clinical interview and child- and parent-endorsement of hoarding obsessions and/or compulsions on Children's Yale-Brown Obsessive Compulsive Scale

comparing children with hoarding vs. those without
age at onset of primary diagnosis of OCD 4 vs. 5 years (p = 0.04)

comorbid diagnosis of generalized anxiety disorder, social anxiety, or separation anxiety in 27.3% vs. 8.6% of children (p = 0.04)

attention deficit hyperactivity disorder diagnosis in 27.3% vs. 5.7% (p = 0.02)

Reference - J Obsessive Compuls Relat Disord 2014 Jan 1;3(1):6
STUDY SUMMARY
younger age at diagnosis appears associated with higher prevalence of comorbid disorders
CROSS-SECTIONAL STUDY: Eur Psychiatry 2008 Apr;23(3):187
based on cross-sectional study

330 patients with OCD were assessed for age at onset and comorbidities

rates of comorbidities were
mood disorders in 70.6%

anxiety disorders in 63.9%

tic disorders in 27.6%

impulse-control disorders in 23.3%

somatoform disorders in 17.3%

substance-related disorders in 15.8%

attention deficit hyperactivity disorder in 13.9%

eating disorders in 10%

age at onset inversely associated with likelihood of comorbidities including
tic disorders (p ≤ 0.001)

anxiety disorders (p = 0.019)

somatoform disorders (p = 0.035)

eating disorders (p = 0.024)

impulse-control disorders (p = 0.028)

female sex associated with anxiety disorders (p = 0.002), eating disorders (p ≤ 0.001), and impulse-control disorders (p = 0.007)

presence of tic disorder associated with comorbid attention deficit hyperactivity disorder (p ≤ 0.001) and anxiety disorders (p = 0.04)

Reference - Eur Psychiatry 2008 Apr;23(3):187

Etiology and Pathogenesis

Pathogenesis

The etiology of OCD is not well understood. Emerging evidence suggests possible interactions among genetic, neurobiological, and environmental factors. Broadly characterized, OCD is a multifactorial condition involving polygenetic and environmental factors leading to neuroanatomical abnormalities (Indian J Psychiatry 2019 Jan;61(Suppl 1):S9).
The neurobiological model of OCD based on structural and functional imaging studies of patients with OCD suggests involvement of extensive networks in the parietal cortex and limbic areas (including the amygdala) and the cerebellum.
- Individuals with OCD may be genetically vulnerable to environmental factors that trigger modification of neurotransmitters, including glutamate, serotonin, dopamine, and Gamma-aminobutyric acid (GABA).
- The neuroanatomical expression of these modifications may result in an imbalance between the direct and indirect loops of the cortico–striato–thalamo–cortical (CSTC) neural circuit. Activation of the aberrant CSTC loop appears to be associated with OCD neuropathology.
- References - Indian J Psychiatry 2019 Jan;61(Suppl 1):S9, Nat Rev Neurosci 2014 Jun;15(6):410
Distinctive brain characteristics in persons with OCD have been reported in mostly case-control imaging studies.
- Grey matter abnormalities associated with OCD in some studies include:
  - Increased grey matter in the caudate nucleus (Pharmacol Ther 2011 Dec;132(3):314)
  - Decreased cortical thickness in the anterior cingulate cortex, orbitofrontal cortex, dorsomedial prefrontal cortex, or parietal regions (Am J Psychiatry 2018 May 1;175(5):453)
  - Decreased volume, thickness, and surface area of the right anterior cingulate gyrus, left frontal pole, and right lateral orbitofrontal cortex (J Psychiatr Res 2012 Sep;46(9):1161)
  - Substantially decreased volume in the smaller hippocampal and larger pallidal areas, with pallidal volume more pronounced in adults with childhood-onset OCD (Am J Psychiatry 2017 Jan 1;174(1):60)
  - Increased thalamic volumes in children with OCD (Am J Psychiatry 2017 Jan 1;174(1):60)
- White matter abnormalities associated with OCD in some studies include:
  - Decreased white matter integrity in the cingulate bundle, corpus callosum, or anterior limb of internal capsule; reported in adult patients with OCD
  - Increased white connectivity; reported in children and adolescents with OCD
  - Reference - J Psychiatr Res 2014 Jul;54:26
- Connectivity abnormalities associated with OCD in some studies include:
  - Hyperactivity in the orbitofrontal cortex, anterior cingulate cortex, and caudate nucleus ( Dev Psychopathol 2008 Fall;20(4):1251)
  - Decreased global brain connectivity around the inferior lateral prefrontal cortex, left middle frontal gyrus, and precentral gyrus (Neuroscientist 2016 Apr;22(2):188)
  - Increased resting-state functional connectivity within the cortico–striato–thalamo–cortical system during resting-state functional magnetic resonance imaging (fMRI) (Front Psychiatry 2019;10:319)
Genome-wide factors associated with OCD and heritability include genetic polymorphisms and gain-of-function variants on specific genes.
- STUDY SUMMARY
  28% common SNP heritability estimated for OCD based on genome-wide complex trait analysis of combined genome-wide association study cohorts
  META-ANALYSIS: Mol Psychiatry 2018 May;23(5):1181
  based on meta-analysis of 2 genome-wide association studies
  
  2,688 individuals of European ancestry with OCD, and 7,037 genomically matched controls from 2 genome-wide association study cohorts were evaluated for association between OCD and 8,693,197 autosomal single nucleotide polymorphisms (SNPs)
  
  no SNP exceeded genome-wide threshold for significance; 130 SNPs observed with p < 1 x 10 ^-5
  
  OCD transmission associated with variants on top haplotype blocks (polymorphisms observed to be inherited together) were
  rs4733767 (p = 7.1 × 10^-7); located in or near cancer susceptibility candidate 8/11CASC8/CASC11 genes
  
  rs1030757 (p = 1.1 × 10^-6); located in glutamate ionotropic receptor delta type subunit 2GRID2 gene
  
  rs12504244 (p = 1.6 × 10^-6); located in KIT proto-oncogene receptor tyrosine kinase KIT gene
  
  28% estimated common SNP heritability for OCD in total study sample based on genome-wide complex trait analysis (GCTA)
  
  CASC8/CASC11 are long noncoding RNAs (lincRNAs); GRID2 encodes a subunit of an ionotropic glutamate receptor; KIT encodes a receptor tyrosine kinase type III, which binds to stem cell factor
  
  Reference - Mol Psychiatry 2018 May;23(5):1181
- STUDY SUMMARY
  SLC1A1 glutamate transporter gene may be associated with OCD
  CASE-CONTROL STUDY: Arch Gen Psychiatry 2006 Jul;63(7):769
  based on case-control study
  
  157 patients (100% white) with OCD and 319 first-degree relatives (49 with OCD and 270 without OCD) had 9 single nucleotide polymorphisms on solute carrier family 1 member 1 (SLC1A1) gene assessed
  
  OCD transmission associated with 2 variants on single haplotype block (polymorphisms that tend to be inherited together)
  rs301434 (p = 0.006)
  
  rs301435 (p = 0.03)
  
  2-marker haplotype within significant block associated with OCD transmission in males (p = 0.005) but not females
  
  SLC1A1 encodes a high-affinity glutamate transporter protein
  
  Reference - Arch Gen Psychiatry 2006 Jul;63(7):769 editorial can be found in Arch Gen Psychiatry 2006 Jul;63(7):717
- STUDY SUMMARY
  DLGAP1 glutamate related synapse gene may be associated with OCD
  CASE-CONTROL STUDY: Mol Psychiatry 2013 Jul;18(7):788
  based on case-control study
  
  1,465 patients with OCD (diagnosis based on DSM-IV criteria), 5,557 ancestry-matched controls, and 400 complete trios were assessed for ancestry-stratified case-control associations between common set of 469,410 autosomal and 9,657 X-chromosome single nucleotide polymorphisms (SNPs)
  
  OCD transmission associated with 2 chromosome 18 SNPs, located within an intron of the disks large-associated protein 1 DLGAP1 gene
  rs11081062 (p = 2.49 × 10^-6)
  
  rs11663827 (p = 3.44 × 10^-6)
  
  DLGAP1 encodes a member of the neuronal postsynaptic density complex
  
  Reference - Mol Psychiatry 2013 Jul;18(7):788
- STUDY SUMMARY
  presynaptic PTPRD gene may be associated with OCD
  CASE-CONTROL STUDY: Mol Psychiatry 2015 Mar;20(3):337
  based on case-control study
  
  1,065 families containing 1,406 patients with OCD, combined with population-based samples resulting in total sample of 5,061 individuals, were assessed for ancestry-stratified case-control association with OCD and single nucleotide polymorphisms (549,123 autosomal markers)
  
  456 markers associated with significance p < 0.001 and 54 markers with significance p < 0.0001
  
  single nucleotide polymorphisms most significantly associated with OCD
  rs4401971 near presynaptic protein tyrosine phosphatase receptor type D PTPRD gene (p = 4.13 × 10⁻⁷)
  
  rs6876547 in region of cadherin clusters near cadherin 9 CDH9 and cadherin 10 CDH10 genes (p = 1.76×10⁻⁶)
  
  other single nucleotide polymorphisms associated with OCD
  rs6452234 in region of cadherin clusters near CDH9 and CDH10 genes (p = 1.13 x 10^-5)
  
  rs3866988 near DLGAP1 gene (p = 2.67 x 10^-4)
  
  presynaptic protein tyrosine phosphatase receptor type D (PTPRD), in association with SLT and NTRK like family member 3 (SLITRK3), promotes differentiation of glutamatergic synapses and selectively regulates development of inhibitory GABAergic synapses
  
  Reference - Mol Psychiatry 2015 Mar;20(3):337
- STUDY SUMMARY
  gain-of-function variant at 5-HTTLPR of serotonin transporter SLC6A4 gene may be associated with OCD in children and adolescents
  CASE-CONTROL STUDY: Neurosci Lett 2014 Sep 19;580:100
  based on case-control study
  
  103 families (103 parent-offspring trios) from children with OCD (mean age 12.8 years) were assessed for association between transmission of gain-of-function variant at 5-HTTLPR in solute carrier family 6 member 4 SLC6A4 gene and OCD in children and adolescents
  included patients with OCD were children and adolescents with age at onset < 18 years (mean age at onset 11 years), and all participants of included trios had European ancestry
  
  all OCD probands fulfilled diagnostic criteria for OCD according to DSM-IV
  
  comorbid disorders in probands included ADHD (10.9%), mood disorders (5.8%), anorexia nervosa (2.5%), tics (10.9%, no Tourette syndrome), phobias (5.9%), and other anxiety disorders (1.7%)
  
  exclusion comorbid disorders in probands included lifetime history of psychotic disorder, Tourette’s syndrome, autistic disorder, alcohol dependence, and intellectual disability
  
  3.8% of mothers and 2.1% of fathers of probands met criteria for OCD
  
  gain-of-function L_A allele at 5-HTTLPR associated increased transmission to affected offspring in OCD-affected child-parents trios (odds ratio 2.06, p = 0.0054)
  
  SLC6A4 encodes an integral membrane protein that transports neurotransmitter serotonin from synaptic spaces into presynaptic neurons
  
  Reference - Neurosci Lett 2014 Sep 19;580:100

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Common compulsions in obsessive-compulsive disorder

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Antidepressant Dosing for OCD in Adults

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Condition

Obsessive-Compulsive Disorder (OCD)

Background Information

Description

Definitions

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Epidemiology

Incidence/Prevalence

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Risk Factors

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Associated Conditions

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Etiology and Pathogenesis

Pathogenesis

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