image: Professor Ian Wong and Dr Adrienne Chan
Credit: Image: Aston University
- Aston University’s Dr Adrienne Chan and Professor Ian Wong led research to map global use of the antiseizure medication
- Valproate is listed as an essential medicine by the World Health Organization but can cause neurodevelopmental disorders when taken by pregnant mothers
- The results suggest progress in access to antiseizure medication in low- and middle-income countries, but use is not always safe.
In a study carried out in collaboration with the World Health Organization, two Aston University academics have found that while access to antiseizure medication in low- and middle-income countries is growing, it is not necessarily always prescribed safely.
Dr Adrienne Chan and Professor Ian Wong led the study to analyse antiseizure medication use across 73 countries between 2012 and 2022 and say that the rise in prescribing is an encouraging sign that access to essential neurological medicines is improving. However, the most widely prescribed is valproate, which can cause birth defects and neurodevelopmental problems in babies if taken by mothers during pregnancy. These can include spina bifida, cleft palate, and intellectual, communication, behaviour and memory disorders.
The World Health Organization (WHO) lists valproate as an “essential medicine” but has issued guidance against prescribing it to women and girls of childbearing age because of the risks of birth defects. It has identified valproate-related foetal disorders as a major global concern.
The researchers say that education is urgently required globally to ensure that the risks are known and alternative medicines are prescribed where necessary. In many high-income countries, tighter regulations and pregnancy prevention programmes have reduced valproate use. In contrast, in countries where newer antiseizure drugs are less affordable or available, valproate continues to be prescribed more frequently.
The WHO commissioned the study led by Dr Chan and Professor Wong as part of ongoing efforts to understand and promote the safe and equitable use of essential neurological medicines worldwide.
The study used sales data from the affected countries, but the researchers say the next step is to understand patterns within specific populations and to evaluate how safety measures are being implemented in different regions. This will give a better understanding of whether such drugs are being prescribed to women of childbearing age and the risks to unborn children.
Dr Chan said:
“Our findings show that access to antiseizure medicines is expanding globally, which is good news for patients who previously had little or no treatment options. But the continued widespread use of valproate in some parts of the world is concerning, given its known risks during pregnancy. Greater global alignment on safe prescribing and education is urgently needed to protect future generations.”
Read the full paper in eClinicalMedicine, part of The Lancet Discovery Science, at https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(25)00491-2/fulltext
Journal
EClinicalMedicine
Method of Research
Data/statistical analysis
Subject of Research
People
Article Title
Antiseizure medications consumption in 73 countries and regions from 2012 to 2022: a longitudinal trend study
Article Publication Date
9-Oct-2025
COI Statement
All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf and declare: AYLC reports grant from the AIR@innoHK programme of the Hong Kong Innovation and Technology Commission; ASCY reports grant from the University College London Hospitals NIHR Biomedical Research Centre, College of Mental Health Pharmacy, and UK Turing Scheme; WCYL reports grant from AIR@InnoHK administered by Innovation and Technology Commission, outside the submitted work. JHC has acted as an investigator for studies with Jazz/GW Pharmaceuticals, Stoke Therapeutics, UCB/Zogenix, Ultragenyx, Encoded, and Vitaflo; has been a speaker and has served on advisory boards for Biocodex, Jazz Pharmaceuticals, Nutricia, Stoke Therapeutics, and UCB (all remuneration has been paid to her department); holds an endowed chair at the University College of London Great Ormond Street Institute of Child Health; has received grants from the National Institute for Health and Care Research (NIHR), the Engineering and Physical Sciences Research Council (EPSRC), the Great Ormond Street Hospital for Children (GOSH) Charity, LifeArc, and Epilepsy Research UK; and her research is supported by the NIHR Great Ormond Street Hospital Biomedical Research Centre. MCW has consulted for Angelini Pharma, EpilepsyGtX, and Seer and has received honoraria from Angelini Pharma, Bioquest, Eisai, and UCB pharma, received payment for expert testimony for Pfizer, act as the Chair of trustees of Epilepsy Research Institute, and owns shares in EpilepsyGtx; MCW is also associated with the following patents: WO2018229254A1, EP3116508A1, US10301263B2, EP2642990B1, CA3064329A1, and WO2023152318A1. ATFH is the Vice President (Western Pacific) of International Bureau for Epilepsy and act as an advisor of Hong Kong Epilepsy Association. KKCM reports grants from the CW Maplethorpe Fellowship, the European Union Horizon 2020, the UK National Institute of Health Research and the Hong Kong Research Grant Council, Hong Kong Innovation and Technology Commission, and reports personal fees from IQVIA, unrelated to the submitted work. ICKW received payment for expert testimony for Appeal Court in Hong Kong; ICKW serves on advisory committees for Member of Hong Kong Pharmacy and Poisons Board, as a member of the Expert Committee on Clinical Events Assessment Following COVID-19 Immunisation in Hong Kong, as a member of the Advisory Panel on COVID-19 Vaccines of the Hong Kong Government, as the non-executive director of Jacobson Pharma Corp. Ltd. In Hong Kong, as the founder and director of Therakind Limited (UK), Advance Data Analytics for Medical Science (ADAMS) Limited (HK) and OCUS Innovation Limited (HK, Ireland, and UK); no other relationships or activities that could appear to have influenced the submitted work. YH, FMCB, NI, and NC declare no competing interests.