The drug atomoxetine and stimulants are the ‘most effective’ treatments for adults with attention deficit hyperactivity disorder (ADHD), a new study has found.

Researchers said their ‘landmark’ systematic review, which included over 14,800 participants, ‘sets a new benchmark’ for treatment of ADHD, and should inform future guidelines.

However, they noted that the study’s applicability to long-term ADHD treatment is ‘limited’ since most evidence focused on treatment effects within 12 weeks.

It found that atomoxetine – a selective noradrenaline reuptake inhibitor (SNRI) – and stimulant drugs such as methylphenidate were the ‘only treatment with proven efficacy in reducing symptoms’ among adults with ADHD, as reported by both doctors and patients.

The 113 randomised controlled trials indicated that these treatments are more effective than non-drug interventions, such as cognitive behavioural therapy (CBT) and mindfulness.

Non-pharmacological treatments ‘showed some efficacy’, according to the study, but not when symptom severity was rated by patients themselves.

According to current estimates, between 2% and 5% of adults globally have ADHD.

The study, which was funded by the National Institute for Health and Care Research (NIHR), looked at the effect of treatments on symptom severity, executive dysfunction, emotional dysregulation, and quality of life.

Dr Edoardo Ostinelli, lead researcher and deputy lead of the Oxford Precision Psychiatry Lab, said there is a ‘pressing need to better understand’ the benefits of ADHD interventions given the ‘concerns around the safety’ of medications.

He added: ‘This network meta-analysis is a pivotal step toward optimising ADHD treatment strategies in adults. By providing a comparative evaluation of pharmacological and non-pharmacological options, it lays the groundwork for more informed, patient-centred care.’

Professor Samuele Cortese, study co-author and NIHR research professor at the University of Southampton, said there is ‘significant variation’ in how ADHD in adults is managed globally.

‘Our study represents the most comprehensive evidence synthesis on the treatments for ADHD and should inform future guidelines,’ he said.

Dr Celso Arango, director at the Institute of Psychiatry and Mental Health at the Hospital General Universitario Gregorio Marañón, said the study ‘highlights a clear shortage of research on ADHD in adulthood’, particularly beyond 12 weeks.

He said the findings are ‘applicable only to short-term treatment’, but noted that its co-development with individuals who have ‘lived experience of ADHD’ makes it ‘highly relevant’.

NHS data in July indicated that there was a substantial increase in the number of medicines prescribed for ADHD in 2023/24, including a 28% rise in adults.

Long waiting lists for adult ADHD services led one GP practice to set up its own service, enabling patients to access diagnosis, titration and alternative prescriptions in the case of shortages through primary care. Earlier this year, The Pharmacist spoke to one practice pharmacist involved.

Shortages have affected ADHD medications this year, while the cost to the NHS of mental health drugs overall has soared.

A version of this article first appeared on our sister publication Pulse.