ADHD and Chronic Pain: Understanding the Link to Physical Health

Attention deficit hyperactivity disorder (ADHD) affects approximately 15.5 million adults and 7 million children in the United States, according to report data. Research indicates these individuals face increased risks for chronic pain, autoimmune disorders, and long COVID, driven by a combination of neuroinflammation and psychological factors.

A study published in April in Scientific Reports analyzed 958 adults with treatment-resistant chronic pain. Researchers found that patients reporting “extremely intense” pain—consistently rated 9 or 10 on a 10-point scale—were more likely to exhibit ADHD symptoms than those with lower pain levels.

Overall, ADHD symptoms appeared approximately twice as frequently in this study group as in the general population. However, it remains unclear if a direct biological link exists or if these correlations stem from chronic stress, poor sleep habits, social difficulties, or medication side effects.

Why is ADHD linked to higher pain intensity?

Adults with ADHD report higher rates of chronic pain and increased intensity in conditions like fibromyalgia, migraines, and chronic lower back pain. Karen Stewart, a clinical psychologist in Huntsville, Alabama, attributes this to impulsivity and cognitive rigidity.

Stewart states that beliefs and reactions can intensify physical suffering. Impulsivity may lead to “catastrophizing,” where a person imagines the worst-case scenario, while cognitive rigidity makes it difficult to dismiss those thoughts, increasing the perception of pain.

Psychiatrist Margo Pumar of San Francisco notes that patients often fear their symptoms will never improve. This mental state can trigger central sensitization, a phenomenon where the nervous system becomes hypersensitive to sensory signals, intensifying discomfort.

Did You Know? A study co-authored by researcher Eugene Merzon found that children diagnosed with ADHD showed elevated inflammatory markers, including higher eosinophil counts, as early as one year of age.

How does neuroinflammation affect the body?

Neuroinflammation occurs when tissues in the brain or spinal cord become inflamed. Eugene Merzon, an ADHD researcher certified by the Israeli Ministry of Health, explains that this inflammation can alter how neurons communicate, leading to executive dysfunction and inattention.

Valentin Dragoi, a neuroscience professor at the Houston Methodist Academic Institute, suggests that continuous inflammation may overstimulate the nervous system. This process could worsen fatigue, memory problems, and pain over time.

Merzon’s research also linked ADHD diagnoses to a higher risk of COVID-19 infection at the start of the pandemic, more severe illness, and a greater likelihood of developing long COVID.

Expert Insight: Samantha Carter suggests that the intersection of neuroinflammation and immune response indicates that ADHD cannot be treated as an isolated brain disorder. The stakes involve a systemic health approach, as the brain’s inflammatory state may predispose the entire body to heightened sensitivity and decreased resilience against viral or autoimmune challenges.

What other health conditions coexist with ADHD?

Jeffrey Newcorn, director of the ADHD and learning disorders division at Mount Sinai in New York, reports that ADHD often coexists with immune function disorders. These include type 1 diabetes, rheumatoid arthritis, asthma, allergies, eczema, and hypothyroidism.

ADHD and Chronic Pain: What Doctors Miss

Similar patterns appear in autoimmune diseases like systemic lupus erythematosus (SLE). Meggan Mackay, a rheumatologist and professor at the Feinstein Institutes for Medical Research, notes that neuropsychiatric lupus can cause “brain fog” similar to ADHD.

Mackay explains that symptoms like memory loss and difficulty concentrating were previously dismissed as emotional reactions to chronic illness, but evidence now suggests neuroinflammation as the cause.

Can ADHD treatments improve physical symptoms?

Research suggests that stimulant medications used for ADHD and certain antidepressants may help improve mood disorders and chronic pain. These treatments may address the overlapping neurological pathways involved in both conditions.

However, Newcorn notes that ADHD makes managing complex health issues more difficult. Executive dysfunction—the struggle to plan, prioritize, and manage time—can make it harder for patients to attend appointments or maintain medication schedules.

Because the science is still developing, future clinical approaches may move toward treating the body as a single integrated system. This shift could lead to more comprehensive care that addresses both neurological and systemic inflammation.

Frequently Asked Questions

How many people in the U.S. have ADHD?
Approximately 15.5 million adults and 7 million children are affected by the condition.

What is central sensitization?
It is a phenomenon where the nervous system becomes hypersensitive to sensory signals, which can intensify the perception of pain and discomfort.

Which immune disorders are linked to ADHD?
According to Jeffrey Newcorn, ADHD may coexist with asthma, allergies, eczema, rheumatoid arthritis, type 1 diabetes, and hypothyroidism.

Do you believe healthcare providers should screen for ADHD more frequently in patients with chronic pain?