ADHD Vs. Schizophrenia: Symptoms And Treatment

ADHD and schizophrenia are both disorders that can affect people’s brains, interactions, and ways of experiencing the world. They may have some similarities, but they also tend to be different in a few key ways. For example, schizophrenia usually involves hallucinations and delusions, whereas ADHD mainly features challenges with hyperactivity, impulsivity, and inattentiveness. Treatment for these disorders often differs as well, although both schizophrenia and ADHD can often be managed with the proper professional support.

What is attention-deficit hyperactivity disorder (ADHD)?

Attention-deficit/hyperactivity disorder (ADHD) can affect people’s abilities to pay attention, control their urges, sit still, and more. Symptoms tend to appear in early childhood, and it is often diagnosed during childhood, typically between ages 4 and 18. , This disorder can cause symptoms of inattentiveness, hyperactivity, and impulsiveness. 

Common attention-deficit hyperactivity disorder (ADHD) symptoms

Inattentive symptoms can include:

• Struggling to pay attention
• Having a hard time staying motivated
• Daydreaming or “spacing out”
• Losing, forgetting, or overlooking things
• Making frequent “careless” mistakes on school or work projects

Hyperactivity and impulsiveness symptoms can include:

• Fidgeting
• Having a hard time relaxing
• Making big decisions on a whim
• Taking needless risks
• Blurting things out or interrupting others

These symptoms can significantly impact a person’s life, make making it harder for people to manage work, school, and relationships. People with ADHD may be at a higher risk of depression and anxiety or a subsequent psychotic disorder. 

Conditions commonly confused with ADHD

Various conditions can be confused with ADHD, which is why getting a differential diagnosis from a qualified healthcare professional can be essential for ensuring proper, timely treatment. Some conditions that may be confused with ADHD may include:

• Absence seizure disorder
• Diabetes
• Thyroid dysfunction
• Sleep deprivation
• Post-concussion states

What is schizophrenia?

Schizophrenia is a severe mental illness that can affect the ways people think and act. While ADHD is typically diagnosed at a younger age, schizophrenia is often diagnosed in young adulthood. It is primarily known for causing psychosis, which can be defined as a state in which someone loses touch with reality. Schizophrenia can also affect people’s moods, movement, and daily routines. Like ADHD, schizophrenia often occurs alongside depression and anxiety disorders.

Symptoms of schizophrenia are often referred to as "positive" or "negative." 

Positive symptoms of schizophrenia

Positive symptoms of schizophrenia can also be called psychotic symptoms and may include those listed below:

• Delusions (false beliefs that others can't change)
• Hallucinations (seeing or hearing things that aren’t there)
• Disorganized thoughts or speech (talking or thinking in ways that don’t make sense)

Negative symptoms of schizophrenia

Negative symptoms of schizophrenia may include the following:

• Lack of motivation to do daily tasks
• Lack of desire to interact with others
• Lack of ability to feel pleasure
• Diminish emotional expression

The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) lays out specific criteria for schizophrenia. The DSM states that a person must experience at least two of these symptoms for the better part of a month, which severely affect their daily functioning, to be diagnosed with the disorder.

Schizophrenia spectrum and other forms

In the DSM-5, schizophrenia is categorized under “Schizophrenia Spectrum and Other Psychotic Disorders.” This class includes other severe forms of psychotic disorders, including:

• Schizophreniform disorder
• Schizoaffective disorder
• Delusional disorder
• Brief psychotic disorder
• Substance/medication-induced psychotic disorder
• Unspecified schizophrenia spectrum and other psychotic disorder

These conditions may also have symptoms that overlap with schizophrenia, as well as other symptoms and diagnostic criteria that determine diagnosis. For example, schizophreniform disorder shares many of the same symptoms as schizophrenia, but only lasts from one to six months, while delusional disorder involves at least one fixed delusion that lasts at least one month but does not have the other prominent psychotic symptoms of schizophrenia. Note that, throughout this article, we will be discussing schizophrenia specifically, not these other conditions on the schizophrenia spectrum.

Conditions commonly confused with schizophrenia

In addition to the above-mentioned conditions, there may be other conditions that are similar to schizophrenia, including: 

• Dissociative identity disorder
• Mood disorders with psychotic features
• Schizoid personality disorder
• Avoidant personality disorder
• Schizotypal personality disorder
• Paranoid personality disorder
• Substance-induced psychotic disorder

Where ADHD and schizophrenia overlap

ADHD and schizophrenia overlap in several ways, including cognitive and emotional challenges as well as risk factors. 

Shared cognitive and emotional challenges

ADHD and schizophrenia may have a few similarities. For instance, both ADHD and schizophrenia can affect people’s executive functioning skills. In general, these are the brain’s abilities to:

• Make plans
• Manage time
• Pay attention
• Control impulses
• Remember information

In people with schizophrenia, issues with executive functionare sometimes called “cognitive symptoms.” They may not be discussed as much as positive and negative symptoms, but, like in ADHD, they can cause challenges in daily life.

ADHD and schizophrenia can also share various emotional challenges, including difficulty with emotional regulation, inner tension, and lower frustration tolerance.

Neurobiology and dopamine differences

ADHD and schizophrenia both involve dopamine dysregulation, but the nature of it differs between the two. Understanding how dopamine functions in each disorder can help explain why they have such distinct symptoms despite having some similarities.

Dopamine levels and brain development

In ADHD, dopamine levels in the prefrontal cortex are generally insufficient, which leads to differences in motivation, attention, and executive function. This may be why stimulant medications, which increase dopamine, are effective for people with ADHD.

In schizophrenia, the role of dopamine is more complex. Dopamine is thought to be too high in some areas of the brain and too low in others. This imbalance is believed to contribute to both the positive and negative symptoms of schizophrenia.

What research still does not fully explain

Although there has been significant research on the topic, it remains unclear how changes in dopamine levels produce such different outcomes and these and other neurodevelopmental disorders. While dopamine appears to play a role in ADHD and schizophrenia, it doesn’t account for every feature of these conditions or how changes in dopamine levels interact with other risk factors to produce such a wide range of symptoms.

Risk factors and family history

Neither ADHD nor schizophrenia has a single cause. Both conditions can arise from a complex combination of factors. Understanding the risk factors associated with each condition can help with early identification and intervention.

Genetic vulnerability and close relatives

Genetics may be likely to raise a person’s risk of developing schizophrenia, as well as other psychiatric disorders, like bipolar disorder. Family history is one of the primary risk factors for ADHD and schizophrenia. Having close relatives with either of these conditions can increase the risk of developing it. 

For example, research shows that genetic vulnerability plays a significant role in schizophrenia; in fact, those with a close family member who has it face a risk that is ten times greater than the general population. As for ADHD, research shows it runs strongly in families, with siblings of those diagnosed having up to a ninefold increased risk compared to the general population.

Environmental influences

Both ADHD and schizophrenia have various environmental risk factors, too, including some that overlap. 

Environmental influences that may increase the risk of ADHD include: 

• Having a family history of autoimmune diseases
• Having a family history of preterm births
• Having a family history of lower birth weight 
• Having parents below age 25
• Having parents with low levels of education
• Being raised by a single parent
• Having a low household income
• Having a mother who smokes
• Being exposed to tobacco before age 1
• Having a higher proportion of serious life events during pregnancy
• Being breastfed for less than four months

Environmental influences that can increase the risk of developing schizophrenia include: 

• Having complications during pregnancy, such as maternal malnutrition or maternal infection
• Having complications during childbirth, particularly those that involve a lack of oxygen
• Having older parents
• Having a history of childhood trauma

Key differences between ADHD and schizophrenia

Despite their similarities, ADHD and schizophrenia tend to be different in several ways. ADHD symptoms usually begin to emerge during childhood. On the other hand, symptoms of schizophrenia don’t usually start until a later age. In men, this is typically between the late teens and mid-20s. Women may not be diagnosed until slightly later, usually in their late 20s to early 30s. 

Attention and cognitive profiles

While ADHD and schizophrenia may both feature attention and cognitive difficulties, they appear differently. 

In ADHD, attention problems may be more likely to stem from difficulties with executive function, focus, and impulse control because the brain has a difficult time regulating and directing attention. 

In schizophrenia, cognitive impairment tends to be more severe, affecting working memory and processing speed. Cognitive deficits in this condition may be linked to the brain's structure and connectivity rather than to difficulties regulating attention.

Reality testing and psychotic symptoms

Reality testing is one of the biggest distinctions between schizophrenia and ADHD. While people with ADHD may have cognitive deficits, specifically around distractibility and impulsiveness, they can distinguish what is real from what isn’t. On the other hand, schizophrenia may commonly feature disruptions in reality testing, such as hallucinations and delusions, that fundamentally change how the person interacts and understands the world around them.

Treatment approaches for schizophrenia

Finally, schizophrenia and ADHD are usually treated differently. To relieve schizophrenia symptoms, medications like antipsychotics are often the first-line treatment. Therapy and ongoing mental health support can also be popular treatments for schizophrenia and other psychotic disorders. Some examples include the following:

• Cognitive behavioral therapy (CBT), which generally aims to identify and change negative thought patterns
• Social skills training, which usually focuses on improving relationships and communication
• Community support programs, which typically aim to help people live independently and function in daily life

Medication and therapy for ADHD

Medication is often a core part of ADHD therapy as well. However, the medications used are different and may include psychostimulant drugs, non-stimulants, or other options. Always consult your doctor or psychiatrist before starting, stopping, or changing the way you take medication. The information in this article is not a replacement for medical advice.

Treatment for both disorders

People with ADHD may also benefit from therapy, such as CBT. Other types of therapy may also be helpful:

• Interpersonal therapy, which usually aims to improve mental health by improving relationships
• Mindfulness-based therapy, which generally focuses on building awareness of thoughts and emotions in the present moment

The right combination of treatments for schizophrenia and ADHD may depend on the person, their doctor, and their needs. 

Getting help for schizophrenia and ADHD

Therapy options for ADHD and schizophrenia

Your doctor may suggest therapy as another step toward improving your daily function and quality of life. However, because ADHD and schizophrenia can affect motivation, this may make it harder to commute to in-person therapy. Online therapy generally empowers you to talk to a licensed therapist from the comfort of your own home. This may be more convenient than in-person therapy if you’re living with a mental illness that affects your motivation. However, please note that individuals currently experiencing acute positive or psychotic symptoms may require in-person care.

Research has shown that online therapy can be effective for treating ADHD, with one study finding that internet-delivered CBT was a “promising treatment for ADHD” and that it led to lower symptom levels sustained after one year. However, please note that online therapy may not be an appropriate choice for individuals currently experiencing acute positive or psychotic symptoms that may require in-person care.