OCD symptoms have two defining features: obsessions (intrusive thoughts) and compulsions (what you do to soothe stress caused by an obsession).

You’re just sitting there minding your own business when a disturbing thought suddenly pops into your mind.

That’s a strange thought. You try to ignore it, as it has no logical basis. But you feel a surge of anxiety. You try to argue with the thought, but the anxiety seems to dig in its heels, making the thought feel even more alarming.

The next day, the strange feeling is still there. Maybe you do something to try to banish or calm the thought, like repeating a phrase in your head or tapping your foot in a certain way.

Your mind suddenly feels like the enemy. The more you try to fight this thought, the stronger it seems to get.

What’s going on?

Obsessive-compulsive disorder (OCD) often starts this way. If you’re experiencing symptoms like this, you’re not alone.

Research suggests OCD affects 1% to 3% of the global population. Here’s what that looks like.

OCD is a chronic condition with two groups of symptoms. These are unwanted thoughts (obsessions) and compulsions.

Symptoms of obsessions

Obsessions are intrusive repetitive thoughts, images, or urges that cause intense stress. The one thing obsessions have in common is that they’re unwanted and often distressing.

According to the Diagnostic and Statistical Manual of Mental Disorders (5th ed.), you’re experiencing obsessive symptoms when:

  • you experience stressful thoughts or urges that keep coming back
  • you have methods for trying to make these thoughts go away or calm the stress related to them

Obsessive thoughts can include many focuses. Some common themes in obsessions related to OCD include anxiety about:

  • contamination
  • religion
  • sexuality
  • doing harm to others or yourself
  • losing control
  • sickness or disease
  • perfection or symmetry

OCD obsessions can vary. If you’re experiencing obsessions but don’t see yours listed, it certainly doesn’t mean you don’t have OCD.

Symptoms of compulsions

The more you fight an obsession, the stronger it might seem to get — and that’s enough to make most people anxious. So where do compulsions come in? If you experience obsessions, you might engage in a compulsion to reduce anxiety caused by the obsession.

But what is a compulsion? In short, compulsions are repetitive thoughts or actions you feel a need to act out when you experience an obsessive thought. You might use compulsions to reduce anxiety about an obsessive thought.

Similar to obsessions, compulsions can come in many forms. Some people might have compulsions to do physical actions. Others may act out compulsions with their thoughts.

Here are some examples of compulsions:

  • excessive praying to prevent harm or ask for forgiveness
  • doing things exactly right to prevent harm (for example, not missing a spot while cleaning the table to prevent contamination or sickness)
  • “canceling” or “undoing” (replacing a negative word with a positive word to cancel out the bad vibes)
  • counting or performing other rituals to prevent harm
  • washing, cleaning, showering, and grooming to avoid contamination
  • constantly checking whether you locked the door or turned off the oven
  • arranging objects until it feels “right”
  • repeating activities until it feels “right”
  • driving back to where you came from to make sure you didn’t hit a pedestrian
  • not using, touching, or wearing certain clothes or objects to prevent harm

Insight and OCD

Very often, people with OCD recognize that their obsessions and compulsions aren’t making any logical sense, but they often feel compelled to do them anyway.

Research suggests that insight plays a large role in how well treatment works for someone with OCD.

When it comes to OCD, insight is defined as the ability to perceive and separate reality from obsessive thoughts.

This can be difficult for many people, as the thoughts and feelings of OCD feel much stronger than their typical thoughts. These obsessions tend to bulldoze over any logical, opposing thoughts.

But having insight into how the condition works rather than getting swept up in what it’s telling you can make treatment easier.

According to the DSM-5, OCD insight is categorized on a scale from good to absent:

  • Good or fair insight. You know that many of the beliefs that come with your OCD symptoms either aren’t true or probably aren’t true.
  • Poor insight. You think many of your OCD-related beliefs are probably true.
  • Absent insight. You believe the thoughts you have related to OCD represent reality.

About 8 in 10 people who have OCD develop it before they reach age 18.

The diagnostic criteria for OCD in children are similar to that of adults. The DSM-5-TR notes that children are less likely to have insight into their obsessions, most likely due to less-developed cognitive skills.

Children with OCD are also more likely to have other related conditions, such as:

Left untreated, a child’s OCD symptoms may come and go but typically remain into adulthood.

PANDAS and PANS

Pediatric autoimmune neuropsychiatric disorders associated with streptococcus (PANDAS) or pediatric acute-onset neuropsychiatric syndrome (PANS) are variations of pediatric OCD.

PANDAS occurs when strep bacteria cause a severe immune reaction in a child, leading to OCD-like symptoms.

The cause of PANS is unknown, but it’s thought to be triggered by:

  • infections
  • metabolic disturbances
  • other inflammatory reactions

The obsessions and compulsions of children and teens with PANDAS or PANS may look the same as childhood-onset OCD, but there are some differences between the two.

Childhood-onset OCD often begins when the child is 8 to 12 years old, and symptoms tend to increase over time. In PANDAS and PANS, children can be anywhere from 4 to 14 years old and experience a sudden onset of symptoms.

Kids with PANDAS or PANS will also have symptoms not usually seen in people with OCD, such as:

OCD often co-occurs with other conditions. It can have overlapping symptoms or similar-looking symptoms with some of these conditions, making it harder to tell them apart.

According to the DSM-5, conditions that can appear alongside OCD include:

  • Body dysmorphic disorder (BDD). A person with BDD might become fixated on a perceived flaw in their appearance.
  • Trichotillomania (hair pulling). This condition involves recurrent, strong urges to pull out hair on the head or other parts of the body.
  • Hoarding disorder. A person with hoarding disorder might feel stress or anxiety about parting with possessions, even seemingly meaningless objects like used napkins.
  • Excoriation (skin picking) disorder. This condition involves repeated picking at the skin despite causing irritation.

Other conditions that often co-occur with OCD but are not considered obsessive-compulsive disorders in the DSM-5 include:

If you have OCD — or think you may have OCD — you’re not alone. OCD is a treatable condition, and many people with it find a treatment approach that relieves their symptoms.

The International OCD Foundation and OCD UK can give you more information about OCD and help you find a therapist.

For some more information about getting a diagnosis, you can check out How Do I Know If I Have Obsessive-Compulsive Disorder? to learn more.