From hoarding to handwashing to forever checking the stove, obsessive-compulsive disorder (OCD) takes many forms. It is an anxiety disorder that traps people in repetitive thoughts and behavioral rituals that can be completely disabling.
Surveys conducted by the National Institute of Mental Health show that 2 percent of the population suffers from OCD—that's more than those who experience other mental illnesses like schizophrenia, bipolar disorder, and panic disorder. OCD might begin in childhood, but it most often manifests during adolescence or early adulthood. Scientists believe that both a neurobiological predisposition and environmental factors jointly cause the unwanted, intrusive thoughts and the compulsive behavior patterns that appease the unwanted thoughts.
Unless treated, the disorder tends to be chronic—lasting for years, even decades—although the severity of the symptoms may wax and wane over the years. Both pharmacological and behavioral approaches have proven effective as treatments; often a combination of both is most helpful. For more on causes, symptoms and treatments, see our Diagnosis Dictionary.