Types of obsessive-compulsive disorder

OCD shows up in different ways, called themes or subtypes. They are not separate illnesses, and one person may have more than one.

Common themes

• Contamination: fear of germs, dirt or illness, with washing and cleaning
• Checking: repeated checking of locks, appliances or safety
• Symmetry and order: need for things to be exact, with arranging and counting
• Harm obsessions: unwanted thoughts of hurting oneself or others, often with mental rituals and avoidance
• Unwanted sexual or taboo thoughts
• Religious or moral (scrupulosity): fear of sin or blasphemy, with prayer rituals and confession
• Hoarding-related: fear of throwing things away
• Relationship OCD: constant doubts about a partner or one's feelings
• "Pure O" (mainly mental rituals): obsessions with hidden mental compulsions, such as reviewing or praying

Related conditions

Body dysmorphic disorder, hoarding disorder, trichotillomania (hair pulling), skin picking and tic disorders are in the same family and are treated by a mental health team.

By age of onset

• Early-onset: in childhood, more common in boys, often with tics