This Month in Psychopharmacology

Why Medical Evaluation Should Be a Part of ADHD Assessment

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder encompassing inattentive and/or hyperactive/impulsive symptoms that must be present before age 12. Not all patients presenting with attentional/cognitive deficits and/or hyperactivity have ADHD. In this review, the author discusses several medical conditions that may present with symptoms resembling those seen in patients with ADHD, including seizure disorders, diabetes mellitus, thyroid dysfunction, sleep deprivation, sleep disordered breathing, traumatic brain injury, inflammatory bowel disease, iron deficiency, and anemia (Table). In addition to the medical conditions that may present with symptoms similar to those in ADHD, there are also psychiatric conditions (e.g., mood disorders) and additional neurological conditions (e.g., early phase dementia) that may present with cognitive impairments similar to those seen in ADHD. The author suggests that the differential diagnosis of ADHD must include a complete medical (as well as psychiatric) work up and evaluation to exclude non-ADHD causes for cognitive dysfunction (including attentional issues) and/or hyperactivity/impulsivity. Furthermore, it is recommended that the DSM-6 include an exclusion in the diagnosis of ADHD if symptoms are attributable to physiological effects of a substance or another medical condition (as is done for e.g., mood disorders). This is especially important given that the misdiagnosis of ADHD, as well as consequent treatment with ADHD medications, may lead to poorer (and in some cases, dire) patient outcomes.

Table: Medical Conditions That May Be Mistaken for ADHD
Symptoms that may be mistaken as ADHD include: Misdiagnosis as ADHD may lead to: Appropriate treatment includes:
Typical Absence Seizures Daydreaming; glazed or spaced-out demeanor; unable to sustain attention Treatment with stimulants, which can increase seizure activity and poor quality of life Anticonvulsants
Diabetes Mellitus Impaired executive function; Lower verbal intelligence; Poor memory; Reduced sustained attention Untreated diabetes (potentially life-threatening) Insulin; Lifestyle interventions
Subclinical Hypothyroidism Mild cognitive impairment; learning difficulties; inattention Untreated hypothyroidism and poor quality of life Levothyroxine may be effective
Hypothyroidism Deficits in verbal memory, intelligence, attention, memory, psychomotor function, and executive function Untreated hypothyroidism and poor quality of life Levothyroxine
Hashimoto Thyroiditis Inability to concentrate; difficulty focusing; executive dysfunction; poor memory Untreated hypothyroidism and poor quality of life Levothyroxine
Sleep Deprivation Impairment in sustained attention; increased impulsivity Treatment with stimulants, which may worsen sleep (or can paradoxically improve sleep in some individuals) Non-pharmacological and pharmacological strategies to improve sleep duration and quality
Sleep-Disordered Breathing Inattention Excessive daytime sleepiness and poor quality of life Devices (e.g., CPAP) and strategies (e.g., side sleeping) to improve breathing during sleep


Sadek J. Brain Sci 2023;13:1522. Abstract

Additional Education and Resources:


Encore Presentation
Biggest Mistakes in Psychopharm
CME/CE Credit: 0.75  |  Expires: April 1, 2026


Video Snippet
Personalized Treatment Strategies for ADHD
CME/CE Credit: 0.50  |  Expires November 27, 2026


Mechanism of Action Animation
Developmental Trajectories of the ADHD Brain
CME/CE credits: 0.5   |   Expires: November 22, 2025


Patient Education
ADHD Neurobiology Coloring Page
Fun and educational patient handouts!