Some epilepsy medications can interact with blood thinners (anticoagulant medications) creating health risks for people taking both forms of medication at the same time, a new study published in JAMA Neurology warns.
An estimated 36,000 people with epilepsy in the UK also have heart conditions requiring treatment with blood thinners. For this group, the form of epilepsy medication can increase risks of health problems such as stroke, heart attack and major bleeding.
Healthcare specialists called this finding a “safety signal” and added that people should not stop taking their epilepsy medications or blood thinners without consulting their doctor.
Blood thinners and epilepsy medications
An international group of researchers from the University of Liverpool in the UK and the University of Zurich in Switzerland, used international electronic health record data from 165 healthcare organisations for the investigation. Of the 2.29 million adults with epilepsy, 9,529 people also took blood thinners and were included in the study.
The group investigated levetiracetam (one of the most commonly-prescribed epilepsy medications), valproate, moderate enzyme-inducing epilepsy medication and strong enzyme-inducing medications, such as carbamazepine and phenytoin, each versus lamotrigine or lacosamide.
The study found that levetiracetam, which more than half of people in the study (57%) were prescribed, increased the risk of stroke, heart attack and other serious blood clots when compared with lamotrigine or lacosamide, as well as the risk of death.
A ‘safety signal’ rather than cause
Study author, senior clinical lecturer at the University of Liverpool and consultant neurologist at The Walton Centre NHS Foundation Trust, Dr Gashirai Mbizvo, said: “Levetiracetam is often favoured in people taking anticoagulants because it has generally been assumed not to interact significantly with these medications.
“Our findings challenge that assumption and suggest that patients taking levetiracetam alongside direct oral anticoagulants may face a substantially higher risk of serious blood clots and death than those taking alternative antiseizure medications.
“Importantly, this study identifies a safety signal rather than proving that levetiracetam directly causes these outcomes. Patients should not stop or change either their antiseizure medication or anticoagulant without medical advice.”
Strong enzyme inducing medications were also found to increase the risk of blood clots but reduce the risk of major bleeding. Meanwhile valproate was found to increase the risk of death and major bleeding.
‘New data into the conversation’
Tom Shillito, health improvement and research manager at Epilepsy Action said: “We welcome this research, which brings new data into the conversation about drug safety. We hope that research continues to bring more understanding and clarity in this area in the future.
“We know it can be a challenge for people with epilepsy to find the right balance with their anti-seizure medication, particularly when they’re managing other health conditions, and so we can understand concerns they may have about these findings.
“If they are worried about what this could mean for their treatment, we advise them to speak to their neurologist about their medication. It’s also really important they do not stop taking their medication until they have sought further advice.
“If people do have any concerns in the meantime, they can contact the Epilepsy Action support line on freephone 0808 800 5050 or visit epilepsy.org.uk.”
Study authors added that further research is now needed to confirm the findings and better understand the reasons for these effects and that the Medicines and Healthcare products Regulatory Agency (MHRA) has been notified of the research.
More articles
