Repurposing amlodipine, a commonly used blood pressure medicine, could help manage attention-deficit/ hyperactivity disorder (ADHD) symptoms, according to an international study involving the University of Surrey.
In a study published in Neuropsychopharmacology , researchers tested five potential drugs in rats bred to exhibit ADHD-like symptoms. Among them, only amlodipine, a common blood pressure medication, significantly reduced hyperactivity.
To confirm its effects the team tested amlodipine in zebrafish, an important model for studying brain function sharing about 70% of genes with humans. The results showed that amlodipine also reduced hyperactivity and impulsivity—core symptoms of ADHD—in these fish. Further analysis of the fish revealed that amlodipine crosses the blood-brain barrier for the first time, meaning it can directly influence brain function.
The researchers then turned to human genetic data and found that, remarkably, ADHD is linked to the same calcium channels in the brain as the targets for amlodipine. This suggests a potential target brain pathway for treatments. Finally, an analysis of UK-wide patient data showed that people taking amlodipine reported fewer mood swings and less risk-taking behaviour, further supporting its potential as a new ADHD treatment.
Dr Matthew Parker, co-author of the study from the University of Surrey, said:
"Repurposing amlodipine, a well-established blood pressure medication, offers a promising and swift pathway to address ADHD symptoms. Our research indicates that, due to its existing approval and safety profile, amlodipine could be rapidly redeployed as a treatment option for ADHD, potentially providing relief to patients sooner than developing new medications."
Current ADHD medications are effective but come with significant side effects: from appetite loss, high blood pressure, headaches and sleep disturbance and carry a risk of misuse. Amlodipine, which is already widely used and well-tolerated, could offer a new, safer treatment option for ADHD.
Around 25% of patients do not respond well to any current ADHD medication, highlighting the urgent need for new treatment options.
