Obsessive-compulsive disorder (OCD) is a mental disorder in which you have thoughts (obsessions) and rituals (compulsions) over and over. They interfere with your life, but you cannot control or stop them.

The cause of obsessive-compulsive disorder (OCD) is unknown. Factors such as genetics, brain biology and chemistry, and your environment may play a role.

Obsessive-compulsive disorder (OCD) usually begins when you are a teen or young adult. Boys often develop OCD at a younger age than girls.

Risk factors for OCD include:

• Family history. People with a first-degree relative (such as a parent, sibling, or child) who has OCD are at higher risk. This is especially true if the relative developed OCD as a child or teen.
• Brain structure and functioning. Imaging studies have shown that people with OCD have differences in certain parts of the brain. Researchers need to do more studies to understand the connection between the brain differences and OCD.
• Childhood trauma, such as child abuse. Some studies have found a link between trauma in childhood and OCD. More research is needed to understand this relationship better.

In some cases, children may develop OCD or OCD symptoms following a streptococcal infection. This is called Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS).

People with OCD may have symptoms of obsessions, compulsions, or both:

• Obsessions are repeated thoughts, urges, or mental images that cause anxiety. They may involve things such as
  • Fear of germs or contamination
  • Fear of losing or misplacing something
  • Worries about harm coming towards yourself or others
  • Unwanted forbidden thoughts involving sex or religion
  • Aggressive thoughts towards yourself or others
  • Needing things lined up exactly or arranged in a particular, precise way
• Compulsions are behaviors that you feel like you need to do over and over to try to reduce your anxiety or stop the obsessive thoughts. Some common compulsions include
  • Excessive cleaning and/or handwashing
  • Repeatedly checking on things, such as whether the door is locked or the oven is off
  • Compulsive counting
  • Ordering and arranging things in a particular, precise way

Some people with OCD also have Tourette syndrome or another tic disorder. Tics are sudden twitches, movements, or sounds that people do over and over. People who have tics cannot stop their body from doing these things.

The first step is to talk with your health care provider about your symptoms. It's important to check whether a physical problem is causing your symptoms. So your provider will do a physical exam and will ask you about your medical history. If your symptoms do not seem to be caused by a physical problem, your provider may do an OCD test or may refer you to a mental health specialist for further evaluation or treatment.

Obsessive-compulsive disorder (OCD) can sometimes be hard to diagnose. Its symptoms are like those of other mental disorders, such as anxiety disorders. It is also possible to have both OCD and another mental disorder.

Not everyone who has obsessions or compulsions has OCD. Your symptoms would usually be considered OCD when you:

• Can't control your thoughts or behaviors, even when you know that they are excessive
• Spend at least 1 hour a day on these thoughts or behaviors
• Don't get pleasure when performing the behaviors. But doing them may briefly give you relief from the anxiety.
• Have significant problems in your daily life because of these thoughts or behaviors

The main treatments for obsessive-compulsive disorder (OCD) are cognitive behavioral therapy, medicines, or both:

• Cognitive behavioral therapy (CBT) is a type of psychotherapy. It teaches you different ways of thinking, behaving, and reacting to your obsessions and compulsions.
  • Exposure and Response Prevention (ERP) s a specific type of CBT. ERP involves gradually exposing you to your fears or obsessions. You learn healthy ways to deal with the anxiety they cause.
• Medicines for OCD include certain types of antidepressants. If those don't work for you, your provider may suggest taking some other type of psychiatric medicine.

If you have severe OCD that does not get better with these treatments, your provider may suggest a treatment called repetitive transcranial magnetic stimulation (rTMS). It is a brain stimulation procedure that uses magnetic waves. It can target specific brain areas associated with OCD.

NIH: National Institute of Mental Health