Can Thyroid Disorders Present with Symptoms Similar to ADHD? 

Thyroid disorders and ADHD can share a range of overlapping symptoms, which sometimes leads to diagnostic confusion. While these conditions are distinct, certain thyroid imbalances, such as hypothyroidism or hyperthyroidism, can present with symptoms that mimic those of ADHD, complicating the differential diagnosis process. 

Symptom Overlap: ADHD vs. Thyroid Disorders 

In hypothyroidism (underactive thyroid), individuals often experience symptoms like fatigue, difficulty concentrating, and memory problems, all of which can resemble the inattention and cognitive difficulties seen in ADHD. Additionally, hypothyroidism may cause irritability, mood swings, and even sluggishness, which could be mistaken for the emotional dysregulation common in ADHD. On the other hand, hyperthyroidism (overactive thyroid) can lead to restlessness, nervousness, and impulsivity, which are also typical traits of ADHD.  

Differential Diagnosis: Thyroid Testing and ADHD 

The key to distinguishing between thyroid disorders and ADHD lies in a comprehensive differential diagnosis. Clinicians may conduct blood tests to check for thyroid hormone levels (such as TSH, T3, and T4) to confirm the presence of a thyroid disorder. If thyroid function is normal, ADHD may be diagnosed based on behavioural assessments, symptom history, and observation of attention and hyperactivity patterns in various settings. 

While thyroid disorders and ADHD can present with similar symptoms, proper testing and a thorough medical evaluation are essential to ensure an accurate diagnosis. Identifying and treating thyroid issues can often alleviate symptoms that overlap with ADHD, improving overall well-being. 

Visit providers like ADHD Certify for personal consultations and expert guidance tailored to your unique situation. 

For a deeper dive into the science, diagnosis, and full treatment landscape, read our complete guide to Differential Diagnosis of ADHD.

Avery Lombardi, MSc

Author

Avery Lombardi is a clinical psychologist with a Master’s in Clinical Psychology and a Bachelor’s in Psychology. She has professional experience in psychological assessment, evidence-based therapy, and research, working with both child and adult populations. Avery has provided clinical services in hospital, educational, and community settings, delivering interventions such as CBT, DBT, and tailored treatment plans for conditions including anxiety, depression, and developmental disorders. She has also contributed to research on self-stigma, self-esteem, and medication adherence in psychotic patients, and has created educational content on ADHD, treatment options, and daily coping strategies.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the author's privacy. 

Dr. Rebecca Fernandez, MBBS

Reviewer

Dr. Rebecca Fernandez is a UK-trained physician with an MBBS and experience in general surgery, cardiology, internal medicine, gynecology, intensive care, and emergency medicine. She has managed critically ill patients, stabilised acute trauma cases, and provided comprehensive inpatient and outpatient care. In psychiatry, Dr. Fernandez has worked with psychotic, mood, anxiety, and substance use disorders, applying evidence-based approaches such as CBT, ACT, and mindfulness-based therapies. Her skills span patient assessment, treatment planning, and the integration of digital health solutions to support mental well-being.

All qualifications and professional experience stated above are authentic and verified by our editorial team. However, pseudonym and image likeness are used to protect the reviewer's privacy.