Is Heart Risk a Concern for ADHD Medication Users?

Do attention-deficit/hyperactivity disorder (ADHD) medications pose a risk to the heart? A new study led by the University of Southampton, published in The Lancet Psychiatry, represents the most comprehensive and rigorous analysis to date addressing this question.

Drawing on data from over 100 clinical trials, researchers found that while ADHD medications are associated with a modest increase in blood pressure and heart rate, these changes are generally small and not clinically concerning.

Understanding ADHD and its treatments

ADHD is a prevalent neurodevelopmental condition characterized by symptoms such as inattention, hyperactivity and impulsivity. Around 8% of children are diagnosed with ADHD worldwide, with a large number receiving pharmacological treatment to manage their symptoms. ​

Medications, particularly stimulants, have been shown to offer substantial benefits. They enhance cognitive functions, leading to improved focus, better academic performance and reduced behavioral issues. These treatments have also been associated with decreased risks of anxiety, depression and other related conditions.

As ADHD diagnoses and treatment rates continue to rise globally, concerns have been raised regarding the cardiovascular safety of ADHD medications. Stimulant medications can elevate heart rate and blood pressure, potentially increasing the risk of adverse cardiovascular events such as hypertension and arrhythmias. These concerns have been significant enough to prompt regulatory agencies to issue warnings about the potential cardiovascular risks associated with stimulant use.

Previous research in this area has yielded mixed results. While some studies have reported an increased risk of cardiovascular events, others have found no significant association. Many of these studies were limited by small sample sizes, short follow-up periods and methodological constraints, making it challenging to draw definitive conclusions. ​

Given the widespread use of ADHD medications and the potential implications for patient safety, there has been a clear need for robust, large-scale studies to provide more definitive evidence.

Largest study to date finds minimal heart risk from ADHD medications

The latest study has brought new clarity to the ongoing debate over the cardiovascular safety of ADHD medications. Pooling data from 102 randomized controlled trials, encompassing 22,702 participants across a wide age range, the team applied an advanced statistical technique known as network meta-analysis. This allowed the researchers to synthesize both direct and indirect comparisons between multiple treatments – even if the treatments haven’t been directly compared in individual trials. They assessed and compared the cardiovascular effects of both stimulant and non-stimulant medications.

Overall, ADHD medications were associated with modest increases in blood pressure and heart rate in both stimulant and non-stimulant drugs.

In children and adolescents, systolic blood pressure increased by up to 1.8 mmHg and heart rate by up to 5.6 bpm depending on the medication. In adults, changes were slightly higher in some cases, though certainty of evidence was lower.

Guanfacine stood out as the only medication associated with decreases in all three cardiovascular markers – systolic and diastolic blood pressure as well as heart rate – particularly in adults, where the drop in systolic blood pressure exceeded 10 mmHg.

Despite popular assumptions that non-stimulants are inherently safer for the heart, the study found no significant difference between the two drug classes in terms of their cardiovascular impact.

The analysis also examined electrocardiogram parameters, such as the QTc interval – a marker often used to evaluate the risk of serious arrhythmias.

Across the board, changes in these measures were minimal and not clinically concerning.

“When it comes to taking any medication, risks and benefits should always be assessed together,” said corresponding author Dr. Samuele Cortese, a professor of child and adolescent psychiatry at the University of Southhampton. “We found an overall small increase in blood pressure and pulse for the majority of children taking ADHD medications.”

“Other studies show clear benefits in terms of reductions in mortality risk and improvement in academic functions, as well as a small increased risk of hypertension, but not other cardiovascular diseases. Overall, the risk-benefit ratio is reassuring for people taking ADHD medications,” he added.

Why cardiovascular monitoring still matters in ADHD treatment

The findings of this large-scale analysis offer reassurance to clinicians, patients and families navigating the complexities of ADHD treatment. While ADHD medications are associated with modest increases in blood pressure and heart rate, these changes are generally small and unlikely to be clinically significant for most individuals. In this context, the study supports the continued use of these medications while reinforcing the importance of routine cardiovascular monitoring across all medication types.

Crucially, the results underscore that both stimulant and non-stimulant medications warrant the same level of scrutiny when it comes to cardiovascular side effects.

“Our findings should inform future clinical guidelines, stressing the need to systematically monitor blood pressure and heart rate, both for stimulants and non-stimulants,” said lead author Dr. Luis Farhat, a researcher at the University of São Paulo, Brazil. “This should be particularly relevant for practitioners who might assume that only stimulants have a negative effect on the cardiovascular system.”

However, the authors also caution that their findings come with important limitations. Most randomized controlled trials included in the analysis were relatively short in duration, typically lasting just weeks to months.

“Our findings, based on randomized controlled trials that tend to be of short duration due to ethical issues, should be complemented by results from real-world, longer-term studies,” said senior author Dr. Alexis Revet, a professor of child and adolescent psychiatry at Toulouse University Hospital.

The next steps for the research team include exploring whether specific individuals or subgroups may be more vulnerable to cardiovascular side effects.

“While our findings are informative at the group level, that is, on average, we cannot exclude that a subgroup of individuals may have a higher risk of more substantial cardiovascular alterations,” said Cortese.

“While it is currently not possible to identify those individuals at higher risk, efforts based on precision medicine approaches will hopefully provide important insights in the future,” he added.

Reference: Farhat LC, Lannes A, Del Giovane C, et al. Comparative cardiovascular safety of medications for attention-deficit hyperactivity disorder in children, adolescents, and adults: a systematic review and network meta-analysis. Lancet Psychiatry. 2025:S2215036625000628. doi: 10.1016/S2215-0366(25)00062-8

This article is a rework of a press release issued by the University of Southampton. Material has been edited for length and content.