Obsessive-Compulsive Disorder (OCD)

Obsessive-Compulsive Disorder (OCD)

1 Overview

Summary and Quick Facts

  • Obsessive-compulsive disorder, or OCD causes uncontrollable recurring thoughts, called obsessions. These obsessions may make one feel like they must repeat certain behaviors, called compulsions.
  • This protocol will help you understand the signs and symptoms of OCD. You’ll also learn about factors that contribute to the condition and what treatments are available.
  • Exercising and learning to deal with stress in a healthy way may reduce some of the symptoms of OCD. Supplementation with N-acetylcysteine (NAC) reduced OCD symptoms, in a clinical trial.

Obsessive-compulsive disorder (OCD) is a type of anxiety disorder in which people suffer from repeated, unwanted thoughts or ideas (obsessions); engage in irrational repetitive behaviors or mental acts (compulsions); or both. Carrying out the compulsive behaviors tends to ease feelings of anxiety, while repressing compulsive behavior causes stress.

Several integrative interventions, such as N-acetylcysteine, glycine, and inositol have been shown to reduce OCD symptoms in clinical trials.

Signs and Symptoms

  • Mental obsessions and behavioral compulsions, with four subtypes:
    • Symmetry or order, things need to be “just so”
    • Forbidden thoughts or images: an affected person will seek reassurance that they are a good person, ask forgiveness and pray
    • Cleaning and fear of contamination
    • Hoarding (listed as a separate mental illness in the latest Diagnostic and Statistical Manual of Mental Disorders [DSM-5])
  • Tics (sudden, brief movements or sounds) or evidence of excessive handwashing may be signs in some cases

Causes and Risk Factors

The causes of OCD are not yet fully understood, but several factors seem to be involved:

  • There may be abnormal structure and activity of certain parts of the brain and of the neurotransmitters serotonin and dopamine in patients with OCD
  • Lower estrogen levels in both men and women are associated with OCD symptoms
  • Life events such as stress or trauma can modify the gene expression of serotonin and dopamine, which may lead to OCD

Conventional and Emerging Therapies

Conventional treatment for OCD includes both pharmacological and non-pharmacological therapy:

  • Cognitive-behavioral therapy, which seems to be more effective than selective serotonin reuptake inhibitors (SSRIs) in patients with OCD
  • SSRIs and the tricyclic antidepressant clomipramine (Anafranil) (a non-selective serotonin reuptake inhibitor, or SRI) are both considered first-line pharmacotherapy for OCD.
  • Deep-brain stimulation involves the surgical implantation of electrodes and is FDA approved to treat chronic and severe cases of OCD.
  • Amisulpride, a second-generation antipsychotic drug that is widely available outside the United States, modulates the action of dopamine in the brain.
  • Repetitive transcranial magnetic stimulation (rTMS) is being investigated for OCD; it involves stimulating specific brain regions through the use of magnetic current.

Dietary and Lifestyle Changes

  • Exercise may reduce anxiety and depression, symptoms that often accompany OCD, and may increase the ability to tolerate normal stress.
  • Stress reduction, as stress may exacerbate OCD because it can reinforce compulsive behavior.

Integrative Interventions

  • Inositol: In a double-blind controlled trial of patients with OCD, oral inositol resulted in a significant reduction in the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) score, while placebo treatment resulted in average Y-BOCS score reductions of less than one point.
  • N-Acetyl L-Cysteine (NAC): In a randomized controlled trial, 48 patients with OCD who had not responded to a 12-week course of high-dose SRI medication received either additive NAC or placebo for an additional 12 weeks. In the NAC group, almost 53% had a full clinical response (defined as a decrease in Y-BOCS score of more than 35%), while only 15% in the placebo group achieved a full clinical response.
  • Glycine: In a randomized controlled trial in OCD patients, very high-dose glycine or placebo was added to ongoing pharmaceutical or behavioral therapy. Patients in the glycine group experienced a mean decrease of over six points in Y-BOCS score compared with a mean one point decrease for those receiving placebo.
  • Milk thistle: A double-blind randomized trial in participants with OCD compared milk thistle extract to fluoxetine (Prozac). Judged on the basis of change in Y-BOCS scores, milk thistle extract and fluoxetine were similarly effective.
  • Valerian: In a placebo-controlled trial of valerian root extract in patients with OCD, those taking valerian showed statistically significant reductions in Y-BOCS scores at four, six, and eight weeks compared with those taking placebo.

2 Introduction

Obsessive-compulsive disorder (OCD) is a type of anxiety disorder in which people suffer from recurrent, unwanted thoughts or ideas (obsessions); engage in repetitive, irrational behaviors or mental acts (compulsions); or both. Among people with OCD, carrying out compulsive behavior tends to ease feelings of anxiety while repressing compulsive behavior causes stress (Sudak 2012; Veale 2014; Yip 2014; Nicholas 2009; Mayo Clinic 2013).

Because the distressing thoughts may be embarrassing or shameful, OCD patients often do not reveal them to healthcare professionals or family members (Yip 2014; Sudak 2012; Veale 2014). This is unfortunate, because not disclosing OCD symptoms to a healthcare provider can delay diagnosis and treatment. In fact, one survey of 701 patients with OCD symptoms found that an average of 10.2 years elapsed between the onset of OCD symptoms and the first attempt to obtain professional help, and an average of 7 additional years elapsed before the patients received effective treatment (Hollander 1997).

Conventional treatment for OCD relies primarily on specific forms of psychotherapy such as cognitive-behavioral therapy (CBT) and exposure-response prevention therapy, as well as serotonin reuptake inhibitor (SRI) medications (Sudak 2012; Yip 2014). Up to 70% of patients experience significant improvement with treatment, though up to 25% of patients receive minimal benefit and many patients never become completely symptom free (Sudak 2012; Pittenger 2011; Yip 2014).

Only about one-third of OCD patients receive evidence-based drug treatment, and less than 10% receive evidence-based psychotherapy (Grant 2014). Many of the psychotropic drugs used in OCD have significant side effect profiles (Soomro 2012), and the outcome of long-term treatment with these medications in OCD has not been firmly established (Soomro 2008).

Novel treatments for OCD have been the subject of recent scientific inquiry. These include transcranial magnetic stimulation, neurofeedback, and remote cognitive-behavioral therapy. Moreover, several integrative interventions, such as N-acetylcysteine, glycine, and inositol have been shown to reduce OCD symptoms in clinical trials.

In this protocol you will learn about some of the suspected causes of OCD, and how to recognize the symptoms and signs of this insidious condition. Conventional diagnosis and treatment of OCD will be outlined, and a number of promising emerging therapies and natural agents that may benefit those with OCD will be described.

3 Signs and Symptoms

The symptoms of OCD are primarily mental obsessions and behavioral compulsions (Seibell 2013; BPS 2006a). The condition has few outward signs: tics (sudden, brief, intermittent movements or sounds) or dermatological evidence of excessive hand washing may be apparent in some cases (Sudak 2012; Veale 2014). Several other psychiatric disorders can cause signs and symptoms similar to those caused by OCD, which can make identification and correct diagnosis of OCD difficult (Glazier 2013).

OCD symptoms have been categorized into four “symptom dimensions,” which can be thought of as subtypes of the condition. These are contamination/cleaning, symmetry, forbidden thoughts, and hoarding, as presented in Table 1 (Gentil 2014; Bloch 2008). The subtypes of OCD have different clinical presentations and responses to treatment (Landeros-Weisenberger 2010; Mataix-Cols 2002; Kichuk 2013).

There are some gender associations with obsession subtypes: men are more likely than women to have forbidden thought obsessions, particularly sexual thoughts (Landeros-Weisenberger 2010), while women are more likely than men to have cleaning obsessions and contamination compulsions (Alonso 2011).

Table 1: The Four Symptom Dimensions of OCD (from Bloch 2008; Leckman 2009; Williams 2013; Torres 2012; Veale 2014; Bratiotis 2009)





Excessive concern with symmetry or order; things need to be “just so”

Ordering, repeating, counting

Forbidden thoughts

Forbidden thoughts or images (aggressive, religious, sexual)

Suppression of unwanted mental images, compulsive avoidance of triggers


Fear of contamination (eg, dirt, germs, bodily fluids, feces, chemicals, dangerous material)

Cleaning or washing compulsion, compulsive avoidance of triggers


Hoarding (ie, collecting or failing to discard useless items to an extent that causes distress or impairs daily activity)


*Hoarding has been categorized as a separate mental illness in the American Psychiatric Association’s most recent Diagnostic and Statistical Manual of Mental Disorders (DSM-5)

Recognizing OCD

OCD can be difficult to recognize because affected individuals often conceal their distress and behaviors from others. However, OCD is characterized by certain cognitive and behavioral patterns. Some of the most common obsessions and their associated compulsions are listed in Table 2.

Table 2: Common obsessions and examples of compulsive responses (Mayo Clinic 2013; Grant 2014)

Example Obsession

Associated Compulsions

Fear of contamination from shaking hands or by touching objects others have touched

Excessive hand washing

Doubts that one has locked the door or turned off the stove

Checking doors repeatedly to make sure they are locked; checking the stove repeatedly to be certain it has been turned off

Severe stress when objects are not orderly or facing a certain way

Arranging items so they all face the same direction

Fear of harming others; recurrent violent images

Seeking reassurance that one is a good person; monitoring news for reports of violent crime

Thoughts about eternal damnation, or that one is immoral

Asking forgiveness or praying

Recurrent anxiety about doing things incorrectly or incompletely

Excessive checking; performing actions in a particular order

Fear of making inappropriate comments in public

Avoidance of social situations

4 Causes and Risk Factors

While the causes of OCD are not fully understood, several genetic, neurobiological, and environmental factors appear to be at least partially involved.

Brain Structure and Function

Multiple neuroimaging and neurophysiology studies have identified abnormal activity in specific regions of the brain in patients with OCD; researchers are also investigating the possibility that structural abnormalities exist in specific parts of the brain in OCD patients. A report of a patient whose severe OCD disappeared after a small stroke destroyed a small, specific part of the brain supports the theory that disturbances in localized brain regions are involved in OCD (Nakao 2014; Pallanti 2011).

Additional support for the central role of the brain in OCD comes from a significant body of evidence that OCD is associated with abnormal activity of the neurotransmitters dopamine and serotonin (Koo 2010; Hesse 2005; Denys 2004). More recent evidence suggests that dysregulation of the excitatory neurotransmitter glutamate may also contribute to OCD (Kellner 2010; Pittenger 2011).

Variants of genes involved in serotonin, glutamate, and dopamine metabolism have been implicated in OCD (Pauls 2014; Delorme 2009; Nicolini 2010). More studies are needed to establish the specific role of particular genes in OCD, and to develop therapies on the basis of these discoveries (Stewart 2013; Mattheisen 2015).

Sex Hormones

In women and men, estrogen and progesterone levels, as well as individual differences in an estrogen receptor gene, have been associated with obsessive-compulsive symptoms (Alonso 2011; Hill 2007; Boon 2011; Avgoustinaki 2012). Estrogens are known to influence neurotransmitter pathways implicated in OCD, including serotonin, dopamine, and glutamate (Alonso 2011).

In one study, women on hormonal contraception consisting of both a progestin (a synthetic, progesterone-like compound) and estrogen exhibited less depression and OCD symptoms than those on progestin-only or no hormone therapy (Young 2007). In a rodent model, progesterone administration reduced OCD-like behavior (Umathe 2009). While there is evidence to suggest that sex hormones may be related to OCD symptoms, further studies are needed to clarify these relationships, and to establish whether manipulating hormone levels will be of therapeutic value for people with OCD.

Other Risk Factors

Stress. Studies have demonstrated that environmental and genetic factors contribute approximately equally to OCD risk. Life events such as stress or trauma may serve as “epigenetic modifiers” (meaning they modify gene expression and function without altering the sequence of specific genes) that impact serotonin, dopamine, and glutaminergic pathways (Pauls 2014; Mataix-Cols 2013; Cath 2008).

Gender. Men and women are equally affected by OCD, though the symptom subtype does differ between genders. Women are more likely than men to exhibit contamination obsessions and cleaning compulsions, and less likely to have sexual or religious obsessions (Labad 2008; Veale 2014; Landeros-Weisenberger 2010).

Age. The average age of OCD onset is early 20s in women and late adolescence in men (Veale 2014). Earlier age at onset is associated with greater incidence of the symmetry subtype, sexual or religious obsessions, and a greater likelihood of tic disorders (Janowitz 2009; Labad 2008).

Family history. OCD risk is markedly higher for first-degree relatives of patients with OCD or Tourette’s syndrome (Yip 2014).

Pregnancy. In a rigorous review of studies on OCD prevalence in women, pregnancy increased the risk of OCD 1.45-fold, and post-partum women were 2.38 times as likely to experience OCD (Russell 2013).

Infection. Rarely, OCD in children appears to be caused by a group A β­hemolytic streptococcal infection that results in a rapid onset of symptoms. This is an autoimmune condition known as “pediatric autoimmune neuropsychiatric disorder associated with Streptococcus infection,” known by the acronym PANDAS. Encephalitis and bacterial or viral infections have also been associated with the onset of OCD (Ercan 2008; Murphy 2010; Yip 2014; Sudak 2012).

Central nervous system trauma or disease. OCD symptoms can sometimes be associated with other neurological conditions, such as stroke, brain tumor, trauma to the frontal lobe, Huntington’s disease, Tourette’s syndrome, frontotemporal dementia, or hypoxia (Pallanti 2011; Veale 2014; Yip 2014).

5 Diagnosis

As is the case for many psychiatric disorders, there is no laboratory test for OCD. There are, however, specific clinical interview and assessment tools designed to aid in diagnosis. Even with the correct clinical diagnostic tools, it can be difficult to distinguish OCD from other psychiatric conditions (Seibell 2013; Sudak 2012).

The difficulty in correctly diagnosing OCD may stem in part from the frequency with which OCD is associated with other psychiatric disorders (Seibell 2013; Sudak 2012). In one study, 92% of patients with a primary diagnosis of OCD had at least one additional psychiatric diagnosis (de Mathis 2013). Nevertheless, in order to make an OCD diagnosis, a clinician must rule out other psychiatric conditions such as depression, anxiety disorder, psychosis, and ADHD (Masi 2006; Yip 2014; Sudak 2012).

Once an OCD diagnosis has been made, severity can be graded using the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Clinical Global Impressions (CGI) scale, or both:

  • The Y-BOCS is a clinician-administered 10-item questionnaire that rates the frequency, severity, and types of symptoms in an OCD patient, and can be used to monitor disease progression or treatment. Y-BOCS scores range from 0 to 40, with 40 being the most severe (Rosario-Campos 2006; Goodman 1989; Farris 2013).
  • The CGI scale can be used to assess the clinical severity of any mental disorder. It scores symptoms on two 7-point scales: severity of symptoms and response to treatment. The CGI usually rates the patient’s symptoms, behavior, and function over the previous seven days (Busner 2007; Seibell 2013).

Diagnostic Criteria for OCD

Both the World Health Organization (International Statistical Classification of Diseases and Related Health Problems; ICD-10) and the American Psychiatric Association (Diagnostic and Statistical Manual of Mental Disorders; DSM-5) have developed diagnostic criteria for OCD.

ICD-10 criteria (National Collaborating Centre for Mental Health 2006):

Obsessional symptoms or compulsive acts or both must be present on most days for at least two successive weeks and be a source of distress or interference with activities. Obsessional symptoms should have the following characteristics:

  1. must be recognized as the individual's own thoughts or impulses;
  2. must be at least one thought or act that is still resisted unsuccessfully, even though others, which the sufferer no longer resists, may be present;
  3. thought of carrying out the act must not in itself be pleasurable (simple relief of tension or anxiety is not regarded as pleasure in this sense);
  4. thoughts, images, or impulses must be unpleasant and repetitive.

DSM-V criteria (APA 2013):

A. Presence of obsessions, compulsions, or both:

Obsessions are defined by (1) and (2):

  1. Recurrent and persistent thoughts, urges, or images that are experienced, at some time during the disturbance, as intrusive and unwanted, and in most individuals cause marked anxiety or distress.
  2. The individual attempts to ignore or suppress such thoughts, urges, or images, or to neutralize them with some other thought or action (by performing a compulsion).

Compulsions are defined by (1) and (2):

  1. Repetitive behaviors (eg, hand washing, ordering, checking) or mental acts (eg, praying, counting, repeating words silently) that the individual feels driven to perform in response to an obsession or according to rules that must be applied rigidly.
  2. The behaviors or mental acts are aimed at preventing or reducing anxiety or distress, or preventing some dreaded event or situation; however, these behaviors or mental acts are not connected in a realistic way with what they are designed to neutralize or prevent, or are clearly excessive. Note: young children may not be able to articulate the aims of these behaviors or mental acts.

B. The obsessions or compulsions are time-consuming, taking more than one hour per day, or cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.

C. The obsessive-compulsive symptoms are not attributable to the physiological effects of a substance (eg, a drug of abuse or a medication) or another medical condition.

D. The disturbance is not better explained by the symptoms of another mental disorder.

6 Conventional Treatment

Conventional treatment for OCD includes both pharmacological and non-pharmacological therapy. These therapies, alone or in combination, can be successful in managing OCD symptoms. However, complete remission of symptoms is rare, and approximately 25% of patients with OCD will receive little if any benefit from conventional OCD therapies (Pittenger 2011).

Cognitive-Behavioral Therapy

Cognitive behavioral therapy (CBT), a specific type of psychotherapy, appears to be roughly as effective for OCD as medication. A rigorous analysis of many studies on behavioral and pharmacotherapy did not find evidence for superiority of pharmacotherapy over behavioral treatment. Importantly, this analysis also did not find that addition of medication to behavioral treatment was associated with an improvement in outcomes, compared with behavioral treatment alone (Romanelli 2014).

Some important limitations to CBT are difficulty accessing treatment (BPS 2006b), patient aversion to the indicated methods, and a high dropout rate. Additionally, the methods are not equally applicable to all symptom dimensions (subtypes). CBT for OCD encompasses two approaches: exposure with response prevention and cognitive therapy (Hebbar 2013; Bonchek 2009; McKay 2015; Ponniah 2013; Grant 2014; Romanelli 2014).

Exposure with response prevention. In this therapy, the patient is guided through exposure to fear- and anxiety-producing situations and stimuli, progressing from least to most distressing. At the same time, the patient refrains from the compulsive behaviors that temporarily relieve anxiety and distress. An important part of this treatment is for the patient to learn that the anxiety and fear pass on their own, and to develop tolerance for this distress (Grant 2014; McKay 2015). Sixty to eighty-five percent of patients improve with exposure-response prevention treatment, although for up to 30% of patients this treatment is not effective, or patients refuse or discontinue treatment due to the anxiety associated with the exposure (Grant 2014; Veale 2014; Yip 2014). Contamination and washing obsessions are the most responsive to this therapy, while hoarding obsession responds poorly (Veale 2014; Yip 2014).

Cognitive therapy. Cognitive therapy helps patients correct their obsessions and compulsions by identifying unrealistic thoughts and beliefs. Unlike exposure-response prevention, cognitive therapy is not aimed at reducing the anxiety associated with a specific situation (eg, handling a dirty object without washing), but rather at challenging the belief that not washing will lead to negative consequences (Grant 2014). Cognitive therapy may be used independently as a therapy for OCD, or as an adjunct to exposure-response prevention. As an adjunct, cognitive therapy may help increase the patient’s ability to tolerate distress, help address dysfunctional beliefs, and help the patient adhere to and remain in treatment (McKay 2015; Whittal 2005; Ponniah 2013).

Pharmacological Therapy

Serotonin reuptake inhibitors. Selective serotonin reuptake inhibitors (SSRIs) and the tricyclic antidepressant clomipramine (Anafranil) (a non-selective serotonin reuptake inhibitor, or SRI) are both considered first-line pharmacotherapy for OCD. However, SSRIs have a more favorable side effect profile than clomipramine, so they are usually the preferred primary medications (Seibell 2013; Kellner 2010; Grant 2014).

The SSRI medications fluvoxamine (Luvox), paroxetine (Paxil), fluoxetine (Prozac), and sertraline (Zoloft) are approved by the Food and Drug Administration (FDA) for use in OCD patients (Sudak 2012), though they have comparable efficacy (Soomro 2012). Although drug treatment of OCD is not proven more effective than behavioral therapy, it is sometimes used as the sole treatment, including in patients who find the idea of behavioral therapy intimidating (Grant 2014).

Roughly 40–65% of OCD patients respond to treatment with clomipramine or an SSRI, with an average improvement in symptom severity of 20–40%. Relatively few patients experience complete remission with drug treatment alone. Also, OCD patients usually need to undergo drug treatment for longer duration and at a higher dose to achieve benefit, compared with patients using these drugs to treat depression. Symptoms of OCD tend to relapse when medication is discontinued, particularly in those on medication for less than two years (Grant 2014). Most studies of pharmacotherapy for OCD have only lasted 8‒12 weeks, though some studies lasting longer than 12 months demonstrated efficacy. Uncertainty remains, however, about adverse effects and the long-term efficacy of SSRIs for OCD, as well as the ideal duration of treatment (NLM 2014; Soomro 2008).

The side effect profile of SSRIs, while better than the tricyclic antidepressant clomipramine, is significant. Almost a quarter of patients taking SSRIs report adverse effects on sexual function, and other commonly reported side effects include sleep problems, tiredness and fatigue, restlessness, dry mouth, nausea, constipation, dizziness, and weight gain (Bet 2013).

Augmentation therapy. Augmentation is the use of additional medications in patients who do not respond to initial therapy with an SRI. This might include the addition of the tricyclic antidepressant clomipramine to treatment with fluoxetine; or the use of second-generation antipsychotic agents such as risperidone (Risperdal) or haloperidol (Haldol), stimulants, and glutamate receptor modulators such as memantine (Namenda) (Pittenger 2011; Walsh 2011; Seibell 2013). Though there are conflicting data on the efficacy of augmentation therapy, and there are no FDA-approved drugs for this purpose, this medication strategy is often part of clinical practice for OCD (Pittenger 2005; Grant 2014; Soomro 2012; Seibell 2013).

Deep-Brain Stimulation

Deep-brain stimulation involves the surgical implantation of electrodes within specific areas of the brain, and electrical stimulation to produce changes in these regions (Hammond 2008; Lapidus 2014; Malaty 2014; Denys 2009). Deep-brain stimulation is FDA approved to treat chronic and severe cases of OCD (Grant 2014), with reports of successful treatment from case reports and small trials (de Koning 2011; Kisely 2014). Deep-brain stimulation is an invasive procedure in which probes are inserted directly into brain tissue, and carries a risk of adverse effects including infection, intracerebral hemorrhage, acute mood changes, and seizures (de Koning 2011).

7 Novel and Emerging Therapies


Amisulpride is a second-generation antipsychotic drug that is widely available outside the United States (Svestka 2007; Szarfman 2006). It blocks the action of dopamine in the brain (Komossa 2010; Schoemaker 1997). In an open-label trial, 10 patients received 200 mg amisulpride as augmentation therapy for six weeks. Average Y-BOCS scores decreased from 25.3 at study entry to 12.2 by the end of the study (Miodownik 2015). An earlier, similarly designed trial in 20 patients used 200‒600 mg per day of amisulpride, in addition to an SSRI, for 12 weeks. Y-BOCS scores decreased from 26.7 at baseline to 12.5 at the end of the study (Metin 2003).

Repetitive Transcranial Magnetic Stimulation

Repetitive transcranial magnetic stimulation (rTMS) is a method of stimulating specific brain regions through the use of magnetic current similar to that used in magnetic resonance imaging (MRI). It is an FDA-approved treatment for major depression in patients who have not responded to at least one antidepressant drug. This procedure does not require anesthesia, and the magnetic pulse penetrates no more than two inches into the brain from a magnetic coil placed over the forehead on the scalp. The mechanism of action of rTMS is not completely understood, but it is thought that because OCD has been associated with increased neural activity in the prefrontal cortex of the brain, the inhibitory effects of magnetic therapy may be beneficial (Blom 2011; NIH 2015; Mayo Clinic 2015).

rTMS is a lower-risk procedure than deep brain stimulation; seizures and hearing damage are the most serious side effects. Selection of the best brain regions for rTMS treatment is an evolving area of investigation, with newer studies finding more effective treatment regimens (Saba 2015; Jaafari 2012; Lapidus 2014). A rigorous analysis of published studies concluded that rTMS is an effective augmentation to SSRI medication, though many authors call for large, randomized trials to fully clarify the value of rTMS in treating OCD (Ma 2014; Jaafari 2012).

Surgical Treatment

Surgical treatments may be considered in extreme, debilitating OCD cases that do not respond to exposure therapy and medication (Yip 2014; Grant 2014).

Ablative neurosurgery. Ablative neurosurgery techniques destroy or “ablate” specific regions or connections in the brain using precisely placed radiofrequency probes (Hariz 2013). Some studies have found ablative neurosurgery an effective treatment for severe, treatment-resistant OCD (Pepper 2015).

Ablative neurosurgery is available only at specialty centers, is not FDA-approved for treatment of OCD, and carries a substantial risk of adverse effects, including postoperative seizures and memory problems (BPS 2006c; Grant 2014; Soomro 2012; Sudak 2012; Rück 2008).

Non-invasive ablative neurosurgery . A newer, non-invasive ablative neurosurgery technique uses an MRI-guided, focused ultrasound device called ExAblate 4000. In one study of four patients, ultrasound ablation resulted in a gradual, 33% average reduction in Y-BOCS scores over the six months following the procedure, along with rapid and substantial improvements in depression and anxiety (61.1% and 69.4% average reductions, respectively) (Jung 2014).


The term “chronotherapy” refers to treatment that interacts with or modulates the body’s sleep-wake cycles (ie, the circadian rhythm). Chronotherapy has been applied to a range of conditions including major depression, high blood pressure, and even cancer (Martiny 2012; Eriguchi 2003; Watanabe 2013). Hormone dysregulation and disordered sleep patterns have been observed in people with OCD symptoms. Also, some evidence suggests OCD may respond to the drug agomelatine, which is chemically related to melatonin, and is considered a melatonergic antidepressant (Dubovsky 2009; Tzavellas 2014; Coles 2011; Lange 2012). In a rigorous review of 12 studies, patients with OCD were found to have shorter duration of sleep and more disordered sleep than healthy controls (Nota 2015). The hormone melatonin and bright light are powerful chronotherapeutic agents (Dodson 2010; Martiny 2015; Portaluppi 2010; Innominato 2010).

A case report of a 54-year old woman who had severe OCD and was treated with chronotherapy shows the promise of this modality. This patient had not responded to medication and psychotherapy. After adjusting her sleep schedule from 6 AM to 1 PM, to 12 AM to 10 AM, she experienced a 43% (15-point) reduction in her Y-BOCS (Coles 2011). Controlled studies on chronotherapy for OCD are still needed.

Remote Cognitive-Behavioral Therapy

Cognitive-behavioral therapy (CBT) is typically delivered face-to-face by a trained psychotherapist. However, technology-based delivery (through the internet, remote communication technologies, or deliverables like DVDs) may improve access to the treatment and may benefit patients reluctant to engage in face-to-face therapy, or unable to conveniently meet with a trained therapist. In a rigorous review of 8 randomized controlled trials, remote technology-based CBT was superior to controls for OCD, with a non-significant difference between therapist- and technology-administered CBT (Dèttore 2015).


Neurofeedback is a form of biofeedback that allows a patient to influence their own brain activity through interaction with an electroencephalogram (EEG) display. This is a non-invasive technique in which, through concentration, a patient can learn to modify dysfunctional brain activity associated with neuropsychological disorders such as OCD (Deng 2014). Three case reports of individuals with moderate-to-severe OCD (Y-BOCS scores 16–26) demonstrated a marked reduction in Y-BOCS scores (Hammond 2005). In a separate review of clinical reports on 36 individuals whose OCD did not respond to pharmacotherapy, neurofeedback treatment (from 9 to 84 sessions, each lasting 60 minutes per day) resulted in clinical improvements in 33 of 36 patients. Nineteen of these patients maintained their improvements for two years after cessation of neurofeedback treatment (Sürmeli 2011).

Mindfulness-Based Cognitive Therapy

Mindfulness is attention to moment-by-moment experience in a non-judgmental way (Chiesa 2011). Mindfulness-based interventions use mindfulness meditation to teach OCD patients to recognize and refocus or “let go” of obsessive intrusions into their thoughts and feelings (Hanstede 2008). Mindfulness exercises can also incorporate yoga, breathing exercises, as well as body-scanning, a technique in which each external body part is mentally “scanned” for sensations like pain or warmth. Mindfulness-based cognitive therapies have been successful in reducing OCD symptoms (as measured by Y-BOCS scores) in multiple case reports and one small study (Hale 2012). In the study, OCD patients were trained to refocus obsessive attention through the use of mindfulness exercises. They were also trained to identify individual OCD triggers and perform mindfulness and attention exercises whenever they noticed obsessive thoughts; two-thirds of patients in the study reported reductions in OCD symptoms (Hertenstein 2012).

8 Lifestyle Considerations

Aerobic Exercise

Exercise may reduce anxiety and depression, symptoms that often accompany OCD, and may increase resiliency to normal stress. Moderate aerobic exercise combined with regular cognitive-behavioral training and incentives (rewards for adhering to the exercise and behavior training programs) produced reductions in OCD symptoms in a study of 15 OCD patients. The symptom reductions persisted through the 6-month follow-up in patients that adhered to the exercise regimen (Brown 2007). A preliminary trial that added a 12-week structured exercise program to cognitive-behavioral therapy for OCD found a robust benefit, which surpassed the effects of CBT alone observed in other studies (Rector 2015). A larger trial of aerobic exercise in 102 OCD patients is currently underway (Abrantes 2012).

Stress Management

Stress may precipitate OCD (Albert 2000; Grisham 2011; Pace 2011; Visser 2014) because it can reinforce compulsive behavior (Pauls 2014). There are many methods that have been used for stress reduction, such as supplementation with the hormone DHEA and maintaining sex hormone balance. For more information, refer to Life Extension’s Stress Management protocol.

9 Integrative Interventions


Inositol is a natural chemical compound common in many foods, and it is also present in relatively high concentrations in the brain, where it plays an important role in cellular communication (Levine 1997; Camfield 2011). Inositol’s therapeutic mechanism of action is not firmly established, but is believed to involve modulation of serotonin activity in the brain (Harvey 2002; Camfield 2011).

In a six-week, double-blind, controlled, crossover trial of 13 patients with OCD, administration of 18 g per day of oral inositol resulted in an average 4-point reduction in Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) scores, while placebo treatment resulted in average Y-BOCS score reductions of less than 1 point (Fux 1996). In an unblinded study of 14 untreated OCD patients, a 12-week treatment with 18 g daily inositol resulted in an average reduction in Y-BOCS score of 10.7 points—a nearly 50% reduction from baseline values—and a clinical response, defined as a reduction of baseline Y-BOCS score by half, was achieved in 57% of study participants (Carey 2004).


N-acetylcysteine (NAC), an amino acid derivative, can inhibit glutamate release from brain cells, aid in cellular and metabolic detoxification, lower homocysteine levels, and boost levels of glutathione, an important neutralizer of potentially damaging cellular metabolic byproducts (De Flora 1995; van Zandwijk 1995; Kasperczyk 2015; Sarris 2012). In a randomized controlled trial, 48 patients with OCD (Y-BOCS score greater than 16) who had not responded to a 12-week course of high-dose SRI medication received either additive NAC or placebo while continuing SRI medication for an additional 12 weeks. Twenty-four patients received NAC (starting at 600 mg per day and increasing to 2400 mg per day by week 3) and twenty-four control subjects received a placebo. In the NAC group, 53% had a full clinical response (defined as a decrease in Y-BOCS score of more than 35%), while only 15% in the placebo group achieved a full clinical response. Total average reductions in Y-BOCS score were 10.9 points for the NAC group and 5.7 points for the control group (Afshar 2012).

A case study of a 58-year old woman with OCD who did not respond to SRI therapy reported that the addition of NAC (beginning with 600 mg daily, and increasing to 3000 mg per day over six weeks, and then continuing at that dose for an additional seven weeks) to fluvoxamine treatment resulted in a clinically significant improvement in OCD symptoms (Lafleur 2005). In this case, a reduction of 8 points on the Y-BOCS scale was noticed after only one week of treatment, which is indicative of a much more rapid treatment response compared with SSRI treatment alone (Camfield 2011).


Glycine is an amino acid capable of modifying the activity of some neurotransmitter systems in the brain. Along with glutamate, glycine binds and activates N-methyl-D-aspartate receptors in the brain; activation of these receptors has an anti-compulsive effect in animal models of OCD (Camfield 2011). In a randomized controlled trial in 24 OCD patients with a Y-BOCS score greater than or equal to 18, very high-dose glycine (60 g/day) or placebo was added to ongoing pharmaceutical or behavioral therapy. Patients in the glycine group experienced an average decrease of over six points in Y-BOCS score compared with an average one point decrease for those receiving placebo. Eight of twelve participants in the glycine group dropped out of the study due to side effects from the large dose of glycine, though two patients who responded to glycine treatment continued to take glycine for over a year (Greenberg 2009).

In a case report of a 22-year old male patient with severe, debilitating OCD and no satisfactory response to SSRIs, five years of glycine treatment led to a large reduction in OCD symptoms, and resumption of education and social life (Cleveland 2009).

Milk Thistle

Milk thistle has been shown in experimental studies to inhibit monoamine oxidase enzymes, and may increase serotonin levels in the cerebral cortex; both of these properties are similar to mechanisms occurring in prescription antidepressants. A double-blind randomized trial in 35 participants with OCD and Y-BOCS scores greater than 20 compared 600 mg of milk thistle extract to 30 mg daily of fluoxetine. Judged on the basis of change in Y-BOCS scores, milk thistle extract and fluoxetine were similarly effective (Camfield 2011; Sayyah 2010; Mazzio 1998).


Valerian root (Valeriana officinalis L.) has historically been used as a sedative, pain reliever, anxiolytic, and migraine treatment; it is thought to act on the GABA neurotransmitter system in the brain. In a placebo-controlled trial of valerian root extract in 31 patients with OCD and Y-BOCS scores greater than 21, those taking 750 mg/day of valerian showed statistically significant reductions in Y-BOCS scores at four, six, and eight weeks compared with those taking placebo (Pakseresht 2011).

St. John’s wort

St. John’s wort (Hypericum perforatum) has been shown to inhibit monoamine reuptake, increase serotonin binding to its cellular receptors, and modulate activity of the hypothalamic-pituitary axis. St. John’s wort has been extensively studied for depression (Sarris 2012). In an open-label uncontrolled trial, 12 OCD patients were given 450 mg of St. John’s wort extract standardized to 0.3% hypericin twice daily for 12 weeks, which produced a significant 7.4 point average reduction in Y-BOCS score (Taylor 2000).

Vitamin B12 and Folate

Vitamin B12 and folate are cofactors in the synthesis of the neurotransmitters serotonin and dopamine (Valizadeh 2011; Atmaca 2005), and vitamin B12 deficiency may be associated with psychiatric disorders (Valizadeh 2011; Upadhyaya 2012; Sahoo 2011). One study found a significantly higher incidence of serum B12 deficiency in OCD patients compared with healthy controls, with 20% of OCD patients showing low B12 levels (Hermesh 1988). Case reports have also described vitamin B12 deficiency in OCD patients (Valizadeh 2011; Sharma 2012).

Two studies identified low levels of folate and significantly higher levels of the amino acid homocysteine in OCD patients compared with healthy controls. One of these studies found that lower folate levels and higher homocysteine levels were associated with higher Y-BOCS scores. The other study found that vitamin B12 levels were lower and homocysteine levels higher in 35 OCD patients compared with healthy controls (Atmaca 2005; Türksoy 2014). Folate and vitamin B12, along with vitamin B6, are able to lower homocysteine levels (Smith 2010).


Some evidence suggests that, compared with healthy individuals, people with OCD may have lower blood levels of zinc, iron, magnesium, and selenium (Shohag 2012; Ozdemir 2009). Studies investigating the role of mineral supplementation in individuals with OCD are needed as available evidence is currently limited. Nevertheless, one small randomized controlled trial did show that supplementation with very high doses of zinc (440 mg/day) plus fluoxetine led to greater reductions in Y-BOCS scores compared to fluoxetine plus placebo in OCD patients (Sayyah 2012). The dosage of zinc used in this study was extremely high, and should not be attempted without close physician supervision.

Additional Support

Several additional natural agents have shown promise in modulating OCD-like behavior in preclinical research, but studies in humans with OCD are needed before the role of these interventions can be clarified.

Probiotics. A rodent model found that the probiotic strain Lactobacillus rhamnosus GG was able to alleviate chemically induced OCD-like behavior, with an effect similar to the SSRI medication fluoxetine (Kantak 2014). The mechanisms by which the gastrointestinal microbiota may influence the central nervous system are not completely understood, but rodent models have shown that an absence of intestinal bacteria can affect the expression of N-methyl-D-aspartate receptors and the production of stress hormones. Additionally, some bacteria and yeast synthesize neurotransmitters and neuromodulators, including dopamine and serotonin; and in mice, a reduction in anxiety-like behavior in response to probiotic administration was demonstrated to be mediated by activity of the vagus nerve, which communicates directly between the gastrointestinal tract and the brain (Bravo 2012; Cryan 2012; Bercik 2011). More studies are needed to clarify the potential of probiotic microorganisms in individuals with OCD.

Ashwagandha (Withania somnifera). Ashwagandha is an Ayurvedic herb with historical usage as an adaptogen that increases resiliency to physical and mental stress (Singh 2011). It has been investigated for its anxiolytic and antidepressant activities in human and animal models (Pratte 2014; Bhattacharya 2000). In a mouse model of OCD-like behavior induced by a neurotoxin, injection of 50 mg/kg of ashwagandha extract reduced this behavior with an efficacy similar to the SSRI fluoxetine (Kaurav 2012).

Saffron. Saffron, a spice derived from the dried stigmas of Crocus sativus L., contains neuroactive compounds that have demonstrated anxiolytic and antidepressant activities in animal models. In multiple randomized controlled trials, saffron extract has shown superior antidepressant effects compared to placebo and efficacy similar to antidepressant medication (Ghasemi 2014; Lopresti 2014; Pitsikas 2008; Hosseinzadeh 2009; Hausenblas 2013; Shahmansouri 2014). In a rodent model of chemically induced OCD, unique water-soluble carotenoids from saffron, called crocins, prevented OCD-like behavior when given as an injection into the abdominal cavity at daily doses ranging from 30‒50 mg/kg (Georgiadou 2012).

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