
What Causes OCD?
The typical dysfunctional thoughts and actions in OCD appear to result from abnormal levels of or defective neurotransmitters in the brain. Neurotransmitters, derived from amino acids, are the signalling molecules used by nerve cells to communicate and coordinate their activities. They mediate all aspects of brain activities, including things like thought formation, memory, emotion, learning, physical movement, and virtually all other brain functions.
Imbalances or disturbances of several of these neurotransmitters appear to be central in the development of OCD. The neurotransmitters that play important roles in OCD include glutamate, gamma-aminobutyric acid (GABA), serotonin (5-HT), dopamine, and to a lesser extent, norepinephrine. These neurotransmitters are the targets for many of the drugs that have been a cornerstone of OCD treatment.
OCD Subtypes
Although patients with OCD share some clinical characteristics, they frequently have symptoms
that are distinctive. Grouping patients according to their principal symptom profile is useful for:
- Scientific inquiry
- Clinical information exchange
- Specific treatment effectiveness
- Providing patients and their families with realistic long-term expectations

Obsessive Thoughts About Contamination, Washing And Cleaning Compulsions
Patients with this subtype have obsessive thoughts that they are contaminated, often from..
Patients with this subtype have obsessive thoughts that they are contaminated, often from their environment. The person with contamination obsessions can be very fearful and anxious, feelings only relieved by washing and/or decontamination compulsions. These rituals may consume many hours throughout the day.

Obsessive Thoughts About Symmetry, Compulsions Of Ordering And Arranging
People in this group suffer from intrusive thoughts that if you fail to properly sort or balan…
People in this group suffer from intrusive thoughts that if you fail to properly sort or balance objects something bad will happen. Examples include the strong need to have pencils all sharpened to exactly the same height, organizing clothing by colour, or to be obsessive about arranging and rearranging the items on your desk in a precise and inflexible manner. Even finding a message or file that was out of place on your desk can cause distress.

Obsessive Thoughts About Doing Harm, Checking Compulsions
This subtype is associated with great anxiety and distress from strong yet irrational beliefs …
This subtype is associated with great anxiety and distress from strong yet irrational beliefs that you failed to do something or made a mistake that could result in harm to yourself or others. Checking compulsions are rituals undertaken repeatedly for reassurance and to relieve the fear and anxiety. Depending on the content of the obsessions, checking can take many forms. Someone might constantly worry that because they did not lock their door, intruders would get in and harm their family. Even if, rationally, they know they locked it, they are still compelled to return to the door and repeatedly check to be sure.

Obsessive Disturbing Thoughts, Mental Compulsions
In this group, the obsessive thoughts usually have unacceptable (“taboo”), religious, sexual…
In this group, the obsessive thoughts usually have unacceptable (“taboo”), religious, sexual, violent, offensive, or impulsive/aggressive themes.

Obsessions with excessive attachments to physical objects; Hoarding compulsions
In this subgroup, individuals usually fear discarding things that might be useful to them so…
In this subgroup, individuals usually fear discarding things that might be useful to them someday, or have difficulty deciding whether to keep or discard items. They typically collect, often in tremendous excess, items such as old newspapers and magazines, bottles and containers, mail, and many more that usually are considered by others to have little to no value. The clutter may accumulate to the point that it can cause fires, unsanitary conditions, loss of a great deal of living space, and accident risks. Compared to other OCD subgroups, hoarders tend to have greater levels of anxiety and are comparatively difficult to treat. At least one-half of hoarders have first-degree family members who demonstrate hoarding-like behaviour. Compared to other forms of OCD, depression and indecisiveness also tend to occur in family members. There also are several other important differences between hoarding and other OCD subgroups. Although the obsessions of other OCD subgroups are typically uncontrollable and unwanted, patients are quite aware of the extent to which their behaviours are abnormal. By contrast, hoarders usually do not perceive their compulsions as problematic or dangerous. This lack of insight is an obstacle to effective cognitive-behavioural therapy (CBT). Research studies have also shown that the areas of the brain associated with the other subgroups are distinctly different to those in the hoarder form. Finally, clinical research studies of the effectiveness of 3 conventional OCD drugs or CBT have shown mixed results, although recent data show superior outcomes when drug and cognitive-behavioural therapies are combined. First line treatmentThe reader must be aware that the following information about treatment options is intended only as a range of treatment approaches available for people with OCD. The goal is to provide an overall understanding of these therapies sufficient to enable more informed interactions with physicians and therapists. The numerous OCD treatment options currently available, and the variability of specific OCD characteristics, are taken into account by physicians and therapists when making treatment recommendations. Better insights into these factors will, hopefully, allow patients and families to be more active participants in discussions and treatment decision-making with their OCD specialists. The two principal types of OCD treatment are cognitive behavioural therapy (CBT) and medication. Evidence of clinical effectiveness has been amply demonstrated for both and each has a role in OCD symptom control. Whether to begin treatment with CBT, medication, or both, depends on the assessment of the type and severity of the OCD, practitioner experience and preference, and patient health and coexisting medical problems. The latter must be considered carefully in order to minimise the risk of treatment noncompliance.