Obsessive Compulsive Disorder is a condition in which there is usually a combination of unreasonable thoughts and fears that lead to behaviors which are done to lessen the burden of those thoughts. In order to be diagnosed with OCD, these thoughts or "obsessions" and the subsequent behaviors called "compulsions" need to occur regularly and at an intensity that the patient feels interferes with their functioning. Usually there is a mix of obsessions and compulsions, but in some forms of OCD, there may be more obsessions or more compulsions.
OCD looks very different for each patient. There are many factors that go into how OCD presents, including the type of OCD, age, the level of family support and comorbid stressors, and comorbid psychiatric disorders. In the popular media, OCD is characterized by someone who is overly fearful of germs and subsequently washes their hands over and over or is obsessive about having things in order. While these can be symptoms of OCD, there are many other kinds of obsessions and compulsions that have nothing to do with cleanliness. A common theme among those who have OCD is that it can take over their thinking at very inopportune times and be close to impossible to control.
An evaluation with a psychiatric practitioner can help confirm a diagnosis of OCD. Therapy with a therapist trained in exposure and response prevention should be part of the initial treatment plan. If symptoms are severe enough, medication management is often considered. Depending on age and how quickly the symptoms came on, laboratory studies can also be helpful in ruling out medical causes of obsessive thinking.