Yes, dyslexia is very common with ADHD. Roughly 20% to 40% of children with ADHD also have reading problems, and the overlap runs both ways: 20% to 40% of children diagnosed with reading difficulties also meet criteria for ADHD. These are among the most frequently co-occurring neurodevelopmental conditions, and the connection is rooted in shared genetics and overlapping brain differences.
How Often the Two Conditions Overlap
The exact numbers depend on how each study defines and measures the conditions, which is why the ranges are broad. Some researchers place the overlap lower: Sally Shaywitz, a leading dyslexia researcher at Yale, has reported that 12% to 24% of people with dyslexia also have ADHD. Other estimates from clinical samples run as high as 45%. What’s consistent across all the data is that having one condition significantly raises the odds of having the other, far beyond what you’d expect by chance alone.
The overlap is especially pronounced with the inattentive presentation of ADHD (the type less associated with hyperactivity and more with difficulty sustaining focus). Children with inattentive ADHD are the most likely to also struggle with reading, which makes sense when you consider how much sustained attention reading demands.
Why They Co-Occur So Often
A 2024 study from the University of Edinburgh found that dyslexia and ADHD share substantial genetic overlap. Researchers identified 49 genetic regions and 174 genes shared between the two conditions, with 40 of those regions and 121 of the genes never previously linked to either disorder. In other words, the co-occurrence isn’t a coincidence or a side effect of one condition causing the other. The two conditions share biological roots at the DNA level.
Brain imaging research tells a similar story. Children with ADHD tend to show reduced activity in certain brain areas involved in attention and self-regulation, while people with dyslexia show reduced activity in the left side of the brain, where reading processing is concentrated. When both conditions are present, these patterns can compound each other.
How the Two Conditions Amplify Each Other
ADHD and dyslexia affect different core processes, but they converge in ways that make daily functioning harder than either condition alone. Dyslexia is fundamentally a difficulty with decoding written language: recognizing letter-sound relationships, reading fluently, and spelling. ADHD disrupts the ability to sustain attention, manage time, and hold information in working memory. When both are present, the challenges stack.
One important finding from brain imaging research: ADHD by itself doesn’t appear to directly worsen reading accuracy or change how reading circuits in the brain activate. What matters more is executive function, the set of mental skills that includes working memory, flexible thinking, and self-control. Children with dyslexia who also have poor executive function (whether or not they formally meet ADHD criteria) show greater impairments in reading fluency and reduced activation in the brain’s left-hemisphere reading network. So the issue isn’t simply “ADHD makes reading worse.” It’s that the executive function deficits common in ADHD create an additional barrier to reading fluently when dyslexia is already present.
This distinction matters because it points toward what kind of support helps most. Improving attention alone won’t fix a reading problem, and phonics instruction alone won’t address distractibility.
Why One Condition Often Masks the Other
Dyslexia and ADHD share enough surface-level symptoms that one can easily hide behind the other. Both conditions affect memory, organization, concentration, and the ability to follow multi-step instructions. A child who can’t finish reading assignments might be labeled inattentive when the real issue is that decoding text is exhausting. Conversely, a child whose reading struggles are recognized early may never get evaluated for ADHD because everyone assumes the attention problems are just frustration with reading.
This masking effect is one reason the conditions are frequently diagnosed years apart. A child might receive an ADHD diagnosis in early elementary school and not get identified with dyslexia until middle school, or vice versa. Each missed diagnosis delays the specific type of support that would help.
How Each Condition Is Identified
ADHD and dyslexia are diagnosed through different processes, and getting evaluated for both is important when either one is suspected. ADHD is typically identified through behavioral assessment: patterns of inattention, hyperactivity, or impulsivity that persist across settings and interfere with functioning.
Dyslexia falls under the clinical category of Specific Learning Disorder with impairment in reading. Diagnosis requires that reading difficulties have persisted for at least six months despite targeted help, that academic skills fall substantially below age expectations based on standardized testing and clinical evaluation, and that the difficulties aren’t better explained by other factors like vision problems, lack of instruction, or intellectual disability. The reading struggles need to show up during school years, though some people don’t experience significant problems until adulthood, when demands on reading and writing increase.
Because the two conditions are so frequently co-occurring, clinicians who evaluate for one should routinely screen for the other. If your child has been diagnosed with ADHD and is struggling with reading despite adequate instruction, a specific learning evaluation is worth pursuing. The reverse is equally true: a child with dyslexia who also has persistent trouble with focus, organization, or impulse control across multiple settings may benefit from an ADHD evaluation.
What Dual Diagnosis Means for Support
When both conditions are present, effective support needs to address each one on its own terms. Dyslexia responds to structured literacy instruction that explicitly teaches the relationships between sounds and letters, builds fluency through practice, and develops reading comprehension strategies. ADHD responds to a combination of environmental structure (breaking tasks into smaller steps, reducing distractions, using external reminders) and, in many cases, medication that improves the ability to sustain attention.
Neither intervention substitutes for the other. Medication for ADHD can help a child sit still and focus long enough to engage with reading instruction, but it won’t teach them to decode words. Likewise, excellent reading support won’t resolve the organizational and attention challenges that spill into every other area of life. The combination matters, and getting both diagnoses on the table early gives families the clearest path to the right set of accommodations and interventions.