Attention deficit hyperactivity disorder (ADHD) and obsessive-compulsive disorder (OCD) are both mental health conditions that can significantly impact an individual’s life. However, there are some crucial differences in how these conditions manifest.

People with OCD tend to have obsessive thoughts, which they try to prevent by engaging in repetitive rituals, or compulsions. In contrast, a person with ADHD typically presents with excessive hyperactivity and impulsivity and difficulty focusing on one task at a time.

Both conditions may require treatment to improve an individual’s quality of life. The treatment may involve medications, cognitive behavioral therapy (CBT), or behavior management.

Keep reading to learn more about the similarities and differences between ADHD and OCD, including symptoms, causes, and treatment options.

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The fundamental natures of ADHD and OCD are very different, and individuals typically exhibit diverse symptoms in each of these mental health conditions.

ADHD

ADHD is an externalizing disorder that affects how individuals outwardly relate to their environment. It can present with either inattention or hyperactivity and impulsivity.

People with ADHD may have highly varying symptoms that do not fit neatly into each category. They may also experience symptoms of both hyperactivity and inattentiveness.

Not everyone with ADHD experiences all potential symptoms. Moreover, ADHD may present differently in females and in adults.

Symptoms of inattention include:

  • becoming easily distracted and having difficulty holding attention
  • being unable to finish tasks due to loss of focus
  • having difficulty with organization and time management
  • avoiding tasks that require a prolonged mental effort
  • appearing not to listen when others are speaking
  • often losing everyday items
  • making “careless” mistakes and being unable to pay attention to detail
  • being forgetful

Symptoms of hyperactivity and impulsivity include:

  • fidgeting and seeming unable to remain still
  • finding it difficult to take turns in activities and conversations
  • speaking and making noises excessively
  • having difficulty being patient

While ADHD comes with many challenges, there are also several potential benefits to having the condition.

OCD

OCD is an internalizing disorder, which means that people with the condition respond to anxiety by turning inward.

Like ADHD, OCD can also present in two different ways — namely, obsessions and compulsions. People living with OCD can have symptoms of obsessions, compulsions, or both.

The symptoms of obsessions include distressing, intrusive, or unwanted thoughts, such as:

  • fear of misplacing something
  • intense focus on exactness
  • unwanted thoughts about religion or sex
  • fear of germs or contamination
  • fear of causing oneself or others harm
  • thoughts involving violence toward oneself or others

Symptoms of compulsions include repetitive patterned behaviors people do in response to anxiety, such as:

  • arranging and ordering things in a particular way
  • excessively cleaning oneself or their environment
  • compulsively counting
  • repeatedly checking appliances, taps, and alarms, for example, for fear of damage or accidents (magical thinking)
  • repeating phrases or numbers, either out loud or in the mind
  • checking feelings or bodily sensations

The causes of ADHD and OCD are potentially different, but they may overlap.

ADHD

We are still learning about the causes and risk factors for ADHD. However, genetics seem to play a significant role in a person’s likelihood of developing the condition.

Potential causes and risk factors include:

Common views include that ADHD can result from watching too much television, eating excessive amounts of sugar, parenting style, or social factors. While research does not support these claims, these factors could make ADHD symptoms worse.

OCD

Doctors do not know the cause of OCD. However, some factors that may contribute to the development of the condition include:

  • genetics
  • environment
  • brain biology and chemistry

Doctors or mental health professionals may use various approaches to diagnose ADHD and OCD.

ADHD

There are several steps to diagnose a person with ADHD, and there is no single test that doctors can use for diagnosis.

Many symptoms of ADHD are similar to those of other health conditions, making it challenging to diagnose ADHD. Conditions with similar symptoms include:

A doctor will start by carrying out a medical exam, including hearing and vision tests, to rule out other problems with similar symptoms.

The diagnostic process also involves a checklist to rate ADHD symptoms. In the case of children, the doctor or mental health practitioner often relies on history from the child’s caregivers, teachers, and the child themself, depending on the child’s age.

OCD

When diagnosing OCD, a doctor first ensures that no other physical problem is causing the symptoms.

Like ADHD, OCD is difficult to diagnose, because many of its symptoms can resemble other mental health conditions. It is also possible that an individual with OCD has additional mental health problems.

Another factor that can make an OCD diagnosis challenging is that not everyone who experiences compulsions or obsessions has OCD.

A doctor or mental health professional diagnoses OCD only if the following are true:

  • A person spends at least 1 hour per day on obsessive or compulsive thoughts or behaviors.
  • They are unable to control these thoughts and behaviors, even though they know they are excessive.
  • The person notes a lack of pleasure when engaging in these behaviors, although they may provide a brief relief from anxiety.
  • The obsessive or compulsive thoughts and behaviors have a significant negative impact on the person’s daily life.

Doctors or mental health practitioners may use various medications and behavioral therapies to address ADHD and OCD symptoms.

ADHD

ADHD treatment often involves a combination of behavioral therapy and medication. For young children, doctors may recommend that the caregivers receive training in behavior management, allowing them to teach their children essential skills.

Behavioral therapy for school-aged children may involve interventions in the classroom or peer interventions that focus on behavior and interactions with those around them.

This may also mean spending time improving the individual’s organizational skills, making it easier for them to navigate academic and work environments in the future.

Medication includes both stimulant and nonstimulant drugs. However, stimulants are the more common medication because they are fast-acting, while nonstimulants take longer to start working.

OCD

The first-line treatment for OCD includes CBT, medication, or a combination of the two.

CBT is a form of psychotherapy that focuses on teaching individuals different ways of behaving, thinking, and reacting to compulsions and obsessions.

One aspect of CBT that therapists use to treat OCD is exposure and response prevention. This involves gradually exposing the individual to their fears or obsessions in a controlled environment. Through this treatment, the person learns healthy ways to deal with the anxiety these fears or obsessions cause.

Furthermore, doctors may prescribe antidepressants for those with OCD. However, if these medications are ineffective, the doctor may suggest a different psychiatric drug.

Relaxation and stress reduction techniques may also help alleviate OCD symptoms.

A person can have both ADHD and OCD, with some evidence suggesting that 11.8% of those with OCD also have ADHD.

If an individual has both ADHD and OCD symptoms from a young age, they are more likely to experience greater OCD severity, persistence of symptoms, and a less favorable prognosis.

When an individual has both OCD and ADHD, the symptoms of their OCD may be more disruptive and impact their quality of life to a greater extent than if they were living with only one of these two mental health conditions.

A variety of treatments and management techniques are available for both conditions.

ADHD and OCD are two mental health conditions that may appear to share some symptoms. However, ADHD is externalizing in nature, affecting how individuals relate to their environment. By contrast, OCD is internalizing in nature, meaning individuals respond to anxiety by turning inward.

Both ADHD and OCD appear to have some genetic link, but experts do not currently know the exact cause of either of these conditions.

Treatment for both ADHD and OCD is similar, consisting of a form of behavioral therapy and medication. However, the goal of behavioral therapy and the type of medication doctors prescribe differ between the two.

A person can have both OCD and ADHD. Individuals with both conditions often experience more severe OCD symptoms but treatments are available for both.