Treatment is similar to that for other forms of obsessive–compulsive disorder. Exposure and response prevention (ERP), a form of behavior therapy, is widely used for OCD in general and may be promising for scrupulosity in particular. ERP is based on the idea that deliberate repeated exposure to obsessional stimuli lessens anxiety, and that avoiding rituals lowers the urge to behave compulsively. For example, with ERP a person obsessed by blasphemous thoughts while reading the Bible would practice reading the Bible. However, ERP is considerably harder to implement than with other disorders, because scrupulosity often involves spiritual issues that are not specific situations and objects. For example, ERP is not appropriate for a man obsessed by feelings that God has rejected and is punishing him. Cognitive therapy may be appropriate when ERP is not feasible. Other therapy strategies include noting contradictions between the compulsive behaviors and moral or religious teachings, and informing individuals that for centuries religious figures have suggested strategies similar to ERP. Religious counseling may be an additional way to readjust beliefs associated with the disorder, though it may also stimulate greater anxiety.

Little evidence is available on the use of medications to treat scrupulosity. Although serotonergic medications are often used to treat OCD, studies of pharmacologic treatment of scrupulosity in particular have produced so few results that even tentative recommendations cannot be made.

Treatment of scrupulosity in children has not been investigated to the extent it has been studied in adults, and one of the factors that makes the treatment difficult is the fine line the therapist must walk between engaging and offending the client.

Many people with sexual obsessions are alarmed that they seem to lose their sex drive. People with OCD may see this as evidence that they no longer have normal sexual attractions and are in fact deviant in some way. Some may wonder if medication is the answer to the problem. Medication is a double-edged sword. Drugs specifically for erectile dysfunction (i.e. Viagra, Cialis) are not the answer for people with untreated OCD. The sexual organs are working properly, but it is the anxiety disorder that interferes with normal libido.

Medications specifically for OCD (typically SSRI medications) will help alleviate the anxiety but will also cause some sexual dysfunction in about a third of patients. For many the relief from the anxiety is enough to overcome the sexual problems caused by the medication. For others, the medication itself makes sex truly impossible. This may be a temporary problem, but if it persists a competent psychiatrist can often adjust the medications to overcome this side-effect.

People with sexual obsessions can devote an excessive amount of time and energy attempting to understand the obsessions. They usually decide they are having these problems because they are defective in some way, and they are often too ashamed to seek help. Because sexual obsessions are not as well-described in the research literature, many therapists may fail to properly diagnose OCD in a client with primary sexual obsessions. Mental health professionals unfamiliar with OCD may even attribute the symptoms to an unconscious wish (typically in the case of psychoanalysts or psychodynamic therapists), sexual identity crisis, or hidden paraphilia. Such a misdiagnosis only panics an already distressed individual. Fortunately, sexual obsessions respond to the same type of effective treatments available for other forms of OCD: cognitive-behavioral therapy and serotonergic antidepressant medications (SSRIs). People with sexual obsessions may, however, need a longer and more aggressive course of treatment.

Cognitive behavioral therapy (CBT) is a newer therapy than exposure therapy, available for those unable or unwilling to undergo exposure therapy. Cognitive therapy has been shown to be useful in reducing intrusive thoughts, but developing a conceptualization of the obsessions and compulsions with the patient is important.

Treatment for intrusive thoughts is similar to treatment for OCD. Exposure and response prevention therapy—also referred to as habituation or desensitization—is useful in treating intrusive thoughts. Mild cases can also be treated with cognitive behavioral therapy, which helps patients identify and manage the unwanted thoughts.

Treatment for perfectionism can be approached from many therapeutic directions. Some examples of psychotherapy include: cognitive-behavioral therapy (the challenging of irrational thoughts and formation of alternative ways of coping and thinking), psychoanalytic therapy (an analysis of underlying motives and issues), group therapy (where two or more clients work with one or more therapists about a specific issue, this is beneficial for those who feel as if they are the only one experiencing a certain problem), humanistic therapy (person-centered therapy where the positive aspects are highlighted), and self-therapy (personal time for the person where journaling, self-discipline, self-monitoring, and honesty with self are essential). Cognitive-behavioral therapy has been shown to successfully help perfectionists in reducing social anxiety, public self-consciousness, and perfectionism. By using this approach, a person can begin to recognize his or her irrational thinking and find an alternative way to approach situations. Cognitive-behavioral therapy is intended to help the person understand that it is okay to make mistakes sometimes and that those mistakes can become lessons learned.

The phenomenological similarity and the suggested common basic biological dynamics of kleptomania and OCD, pathological gambling and trichotillomania gave rise to the theory that the similar groups of medications could be used in all these conditions. Consequently, the primary use of selective serotonin reuptake inhibitor (SSRI) group, which is a form of antidepressant, has been used in kleptomania and other impulse control disorders such as binge eating and OCD. Electroconvulsive therapy (ECT), lithium and valproic acid (sodium valproate) have been used as well.

The SSRI's usage is due to the assumption that the biological dynamics of these conditions derives from low levels of serotonin in brain synapses, and that the efficacy of this type of therapy will be relevant to kleptomania and to other comorbid conditions.

Opioid receptor antagonists are regarded as practical in lessening urge-related symptoms, which is a central part of impulse control disorders; for this reason, they are used in treatment of substance abuse. This quality makes them helpful in treating kleptomania and impulse control disorders in general. The most frequently used drug is naltrexone, a long-acting competitive antagonist. Naltrexone acts mainly at μ-receptors, but also antagonises κ- and λ-receptors.

There have been no controlled studies of the psycho-pharmacological treatment of kleptomania. This could be as a consequence of kleptomania being a rare phenomenon and the difficulty in achieving a large enough sample. Facts about this issue come largely from case reports or from bits and pieces gathered from a comparatively small number of cases enclosed in a group series.

Obsessive-compulsive disorders are treated with various serotonergic antidepressants including the tricyclic antidepressant clomipramine and various SSRI medications. With existing drug therapy, OCD symptoms can be controlled, but not cured. Several of these compounds (including paroxetine, which has an FDA indication) have been tested successfully in conjunction with OCD hoarding.

Primarily cognitive obsessive-compulsive disorder (also commonly called "primarily obsessional OCD", purely obsessional OCD, Pure-O, OCD without overt compulsions or with covert compulsions) is a lesser-known form or manifestation of OCD. For people with primarily obsessional OCD, there are fewer observable compulsions, compared to those commonly seen with the typical form of OCD (checking, counting, hand-washing, etc.). While ritualizing and neutralizing behaviors do take place, they are mostly cognitive in nature, involving mental avoidance and excessiverumination. Primarily obsessional OCD often takes the form of intrusive thoughts of a distressing or violent nature.

The prevalence of scrupulosity is speculative. Available data do not permit reliable estimates, and available analyses mostly disregard associations with age or with gender, and have not reliably addressed associations with geography or ethnicity. Available data suggest that the prevalence of obsessive–compulsive disorder does not differ by culture, except where prevalence rates differ for all psychiatric disorders. No association between OCD and depth of religious beliefs has been demonstrated, although data are scarce. There are large regional differences in the percentage of OCD patients who have religious obsessions or compulsions, ranging from 0–7% in countries like the U.K. and Singapore, to 40–60% in traditional Muslim and orthodox Jewish populations.

Treatment for OCPD includes psychotherapy, cognitive behavioral therapy, behavior therapy or self-help. Medication may be prescribed. In behavior therapy, a person with OCPD discusses with a psychotherapist ways of changing compulsions into healthier, productive behaviors. Cognitive analytic therapy is an effective form of behavior therapy.

Treatment is complicated if the person does not accept that they have OCPD, or believes that their thoughts or behaviors are in some sense correct and therefore should not be changed. Medication alone is generally not indicated for this personality disorder. Selective serotonin reuptake inhibitors (SSRIs) may be useful in addition to psychotherapy by helping the person with OCPD be less bogged down by minor details, and to lessen how rigid they are.

People with OCPD are three times more likely to receive individual psychotherapy than people with major depressive disorder. There are higher rates of primary care utilization. There are no known properly controlled studies of treatment options for OCPD. More research is needed to explore better treatment options.

Obsessive love is a condition in which one person feels an overwhelming obsessive desire to possess and protect another person toward whom one feels a strong attraction, with an inability to accept failure or rejection. Although not categorized specifically under any specific mental diagnosis by the DSM-5, some people argue that obsessive love is considered to be a mental illness similar to attachment disorder, borderline personality disorder, and erotomania. Depending on the intensity of their attraction, obsessive lovers may feel entirely unable to restrain themselves from extreme behaviors such as acts of violence toward themselves or others. Obsessive love can have its roots in childhood trauma, and may begin at first sight; it may persist indefinitely, sometimes requiring psychotherapy.

Obsessive love occurs in both women and men, making it a gender neutral phenomenon.

Cognitive-behavioural therapy (CBT) has primarily substituted the psychoanalytic and dynamic approach in the treatment of kleptomania. Numerous behavioural approaches have been recommended as helpful according to several cases stated in the literature. They include: hidden sensitisation by unpleasant images of nausea and vomiting, aversion therapy (for example, aversive holding of breath to achieve a slightly painful feeling every time a desire to steal or the act is imagined), and systematic desensitisation. In certain instances, the use of combining several methods such as hidden sensitisation along with exposure and response prevention were applied. Even though the approaches used in CBT need more research and investigation in kleptomania, success in combining these methods with medication was illustrated over the use of drug treatment as the single method of treatment.

In psychology, relationship obsessive–compulsive disorder (ROCD) is a form of obsessive-compulsive disorder focusing on intimate relationships (whether romantic or non-romantic). Such obsessions can become extremely distressing and debilitating, having negative impacts on relationships functioning.

Not only are there significant health risks associated with compulsive hoarding, but scientists are also trying to pinpoint how significant the interference is with occupational and social functioning in a hoarder's daily life. In a pool of compulsive hoarders, 42% found their behavior problematic to the 63% of their family and friends who saw the behavior as problematic. The findings suggest that individuals who hoard may exhibit impaired sensitivity to their own and others’ emotions, and conversely, relate the world around them by forming attachments to possessions rather than to people. Lower emotional intelligence among hoarding patients may also impact their ability to discard and organize their possessions. With such detrimental characteristics, comprehensive research has been performed to find a cure. Although this is ongoing research, most investigations have found that only a third of patients who hoard show an adequate response to these medications and therapeutic interventions.

With the modifications to the DSM, insurance coverage for treatments will change as well as special education programs.

The naturally occurring sugar inositol has been suggested as a treatment for OCD.

Nutrition deficiencies may also contribute to OCD and other mental disorders. Vitamin and mineral supplements may aid in such disorders and provide nutrients necessary for proper mental functioning.

μ-Opioids, such as hydrocodone and tramadol, may improve OCD symptoms. Administration of opiate treatment may be contraindicated in individuals concurrently taking CYP2D6 inhibitors such as fluoxetine and paroxetine.

Much current research is devoted to the therapeutic potential of the agents that affect the release of the neurotransmitter glutamate or the binding to its receptors. These include riluzole, memantine, gabapentin, N-acetylcysteine, topiramate and lamotrigine.

Those suffering from primarily obsessional OCD might appear normal and high-functioning, yet spend a great deal of time ruminating, trying to solve or answer any of the questions that cause them distress. Very often, Pure O sufferers are dealing with considerable guilt and anxiety. Ruminations may include trying to think about something 'in the right way' in an attempt to relieve this distress.

For example, an intrusive thought "I could just kill Bill with this steak knife" is followed by a catastrophic misinterpretation of the thought, i.e. "How could I have such a thought? Deep down, I must be a psychopath." This might lead a person to continually surf the Internet, reading numerous articles on defining psychopathy. This reassurance-seeking ritual will, ironically, provide no further clarification and could exacerbate the intensity of the search for the answer. There are numerous corresponding cognitive biases present, including thought-action fusion, over-importance of thoughts, and need for control over thoughts.

Despite how real and imposing the intrusive thoughts may be to an individual, the sufferer will probably never carry out actions related to these thoughts, even if one believes themselves capable of doing so. One of the reasons for this is because the person in question will go to extreme lengths to avoid circumstances which could trigger their intrusive thoughts.

The disorder is particularly easy to miss by many well-trained clinicians, as it closely resembles markers of generalized anxiety disorder and does not include observable, compulsive behaviors. Clinical "success" is reached when the sufferer becomes indifferent to the need to answer the question. While many clinicians will mistakenly offer reassurance and try to help their patient achieve a definitive answer (an unfortunate consequence of therapists treating primarily obsessional OCD as generalized anxiety disorder), this method only contributes to the intensity or length of the patient's rumination, as the neuropathways of the OCD brain will predictably come up with creative ways to "trick" the person out of reassurance, negating any temporary relief and perpetuating the cycle of obsessing.

The most effective treatment for primarily obsessional OCD appears to be cognitive-behavioral therapy. (more specifically exposure and response prevention (ERP)) as well as cognitive therapy (CT) which may or may not be combined with the use of medication, such as SSRIs. People suffering from OCD without overt compulsions are considered by some researchers more refractory towards ERP compared to other OCD sufferers and therefore ERP can prove less successful than CT.

ERP of Pure-O is theoretically based on the principles of classical conditioning and extinction. The spike often presents itself as a paramount question or disastrous scenario. A response that answers the spike in a way that leaves ambiguity is sometimes warranted. "If I don't remember what I had for breakfast yesterday my mother will die of cancer!" Using the antidote procedure, a cognitive response would be one in which the subject accepts this possibility and is willing to take the risk of his mother dying of cancer or the question recurring for eternity. No effort is expended in directly answering the question in an effort to find resolution. In another example, the spike would be, "Maybe I said something offensive to my boss yesterday." A recommended response would be, "Maybe I did. I'll live with the possibility and take the risk he'll fire me tomorrow." Using this procedure, it is imperative that the distinction be made between the therapeutic response and rumination. The therapeutic response does not seek to answer the question but to accept the uncertainty of the unsolved dilemma.

Acceptance and commitment therapy (ACT) is a newer approach that also is used to treat purely obsessional OCD, as well as other mental disorders such as anxiety and clinical depression. Mindfulness-based stress reduction (MBSR) may also be helpful for breaking out of the ruminative thinking process.

Perfectionists strain compulsively and unceasingly toward unobtainable goals, and measure their self-worth by productivity and accomplishment. Pressuring oneself to achieve unrealistic goals inevitably sets the person up for disappointment. Perfectionists tend to be harsh critics of themselves when they fail to meet their standards.

Currently, genetic research for the understanding of the development of personality disorders is severely lacking. However, there are a few possible risk factors currently in discovery. Researchers are currently looking into genetic mechanisms for traits such as aggression, fear and anxiety, which are associated with diagnosed individuals. More research is being conducted into disorder specific mechanisms.

Egomania is also known as an obsessive preoccupation with one's self and applies to someone who follows their own ungoverned impulses and is possessed by delusions of personal greatness and feels a lack of appreciation. Someone suffering from this extreme egocentric focus is an egomaniac. The condition is psychologically abnormal.

The term "egomania" is often used by laypersons in a pejorative fashion to describe an individual who is intolerably self-centred. The clinical condition that most resembles the popular conception of egomania is narcissistic personality disorder.

The cause of OCPD is unknown. However, it is believed to involve a combination of genetic and environmental factors. Under the genetic theory, people with a form of the DRD3 gene will probably develop OCPD and depression, particularly if they are male. But genetic concomitants may lie dormant until triggered by events in the lives of those who are predisposed to OCPD. These events could include trauma faced during childhood, such as physical, emotional, or sexual abuse, or other psychological trauma. Under the environmental theory, OCPD is a learned behavior.

Like other forms of OCD, psychological and biological factors are believed to play a role in the development and maintenance of ROCD. In addition to the maladaptive ways of thinking and behaving identified as important in OCD, models of ROCD suggest that over-reliance on intimate-relationships or the perceived value of the partner for a person's feelings of self-worth and fear of abandonment (also see attachment theory) may increase vulnerability and maintain ROCD symptoms.

There are many different forms (modalities) of treatment used for personality disorders:

- Individual psychotherapy has been a mainstay of treatment. There are long-term and short-term (brief) forms.

- Family therapy, including couples therapy.

- Group therapy for personality dysfunction is probably the second most used.

- Psychological-education may be used as an addition.

- Self-help groups may provide resources for personality disorders.

- Psychiatric medications for treating symptoms of personality dysfunction or co-occurring conditions.

- Milieu therapy, a kind of group-based residential approach, has a history of use in treating personality disorders, including therapeutic communities.

- The practice of mindfulness that includes developing the ability to be nonjudgmentally aware of unpleasant emotions appears to be a promising clinical tool for managing different types of personality disorders.

There are different specific theories or schools of therapy within many of these modalities. They may, for example, emphasize psychodynamic techniques, or cognitive or behavioral techniques. In clinical practice, many therapists use an 'eclectic' approach, taking elements of different schools as and when they seem to fit to an individual client. There is also often a focus on common themes that seem to be beneficial regardless of techniques, including attributes of the therapist (e.g. trustworthiness, competence, caring), processes afforded to the client (e.g. ability to express and confide difficulties and emotions), and the match between the two (e.g. aiming for mutual respect, trust and boundaries).

Compulsive decluttering is a pattern of behavior that is characterized by an excessive desire to discard objects in one's home and living areas. Other terms for such behavior includes obsessive compulsive spartanism. The homes of compulsive declutterers are often empty. It is the antonym of compulsive hoarding.

The core symptom of the disorder is that the sufferer holds an unshakable belief that another person is secretly in love with them. In some cases, the sufferer may believe several people at once are "secret admirers". The sufferer may also experience other types of delusions concurrently with erotomania, such as delusions of reference, wherein the perceived admirer secretly communicates his or her love by subtle methods such as body posture, arrangement of household objects, and other seemingly innocuous acts (or, if the person is a public figure, through clues in the media). Erotomanic delusions are typically found as the primary symptom of a delusional disorder or in the context of schizophrenia and may be treated with atypical antipsychotics.