Obsessive-compulsive disorder usually includes both obsessions and compulsions. But it's also possible to have only obsession symptoms or only compulsion symptoms. You may or may not realize that your obsessions and compulsions are excessive or unreasonable, but they take up a great deal of time and interfere with your daily routine and social, school or work functioning. Obsession symptoms OCD obsessions are repeated, persistent and unwanted thoughts, urges or images that are intrusive and cause distress or anxiety. You might try to ignore them or get rid of them by performing a compulsive behavior or ritual. These obsessions typically intrude when you're trying to think of or do other things. OCD Obsessions often have themes to them, such as: 
Fear of contamination or dirt
Doubting and having difficulty tolerating uncertainty
Needing things orderly and symmetrical
Aggressive or horrific thoughts about losing control and harming yourself or others
Unwanted thoughts, including aggression, or sexual or religious subjects
 Examples of obsession signs and symptoms include: 
Fear of being contaminated by touching objects others have touched
Doubts that you've locked the door or turned off the stove
Intense stress when objects aren't orderly or facing a certain way
Images of driving your car into a crowd of people
Thoughts about shouting obscenities or acting inappropriately in public
Unpleasant sexual images
Avoidance of situations that can trigger obsessions, such as shaking hands
 Compulsion symptoms OCD compulsions are repetitive behaviors that you feel driven to perform. These repetitive behaviors or mental acts are meant to reduce anxiety related to your obsessions or prevent something bad from happening. However, engaging in the compulsions brings no pleasure and may offer only a temporary relief from anxiety. OCD You may make up rules or rituals to follow that help control your anxiety when you're having obsessive thoughts. These compulsions are excessive and often are not realistically related to the problem they're intended to fix. As with obsessions, compulsions typically have themes, such as: 
Washing and cleaning
Checking
Counting
Orderliness
Following a strict routine
Demanding reassurance
 Examples of compulsion signs and symptoms include: 
Hand-washing until your skin becomes raw
Checking doors repeatedly to make sure they're locked
Checking the stove repeatedly to make sure it's off
Counting in certain patterns
Silently repeating a prayer, word or phrase
Arranging your canned goods to face the same way
 Severity varies OCD usually begins in the teen or young adult years, but it can start in childhood. Symptoms usually begin gradually and tend to vary in severity throughout life. The types of obsessions and compulsions you experience can also change over time. Symptoms generally worsen when you experience greater stress. OCD, usually considered a lifelong disorder, can have mild to moderate symptoms or be so severe and time-consuming that it becomes disabling.