A sweeping international analysis has shed new light on how the selection of antiseizure medications (ASMs) impacts the risk of dangerous blood clots in adults with epilepsy who are also treated with direct oral anticoagulants (DOACs). The study, which drew on electronic health record data from 2.29 million adults with epilepsy, ultimately included 9,529 individuals initiating DOAC treatment, with a mean age of 63 years and a near-even split between men and women.
Researchers compared levetiracetam, valproate, moderate and strong enzyme-inducing antiseizure drugs to a reference group of patients using lamotrigine or lacosamide. The findings? Levetiracetam stood out for all the wrong reasons: it was associated with a higher risk of thromboembolic events—meaning blood clots that can cause stroke or other complications—compared to the reference group. Notably, for adults instead taking vitamin K antagonists (a different class of blood thinners), the risk of blood clots was almost negligible.
Medication Choice: Not Just a Detail
The study’s authors emphasized that the choice of ASM isn’t just a matter of seizure control; it’s a potentially modifiable factor that can influence life-and-death outcomes for people with epilepsy on blood thinners. With 17 drugs now approved for focal seizures—the most common epilepsy type—clinicians and patients have more options than ever, but also more complexity in balancing seizure prevention with the risks of bleeding and clots.
New Drugs, New Hope?
Meanwhile, innovation in epilepsy treatment continues. Xenon’s XEN1101 is being tested in two major phase 3 trials for adults with focal seizures, aiming to offer a new option that avoids some of the drawbacks of older potassium channel modulators. For rare, severe forms like KCNT1-related epilepsy, Actio Biosciences has launched early-phase trials of ABS-1230, with preliminary data suggesting good tolerability in healthy volunteers, though safety in children with complex epilepsy remains to be seen.
The upshot: For adults with epilepsy, especially those on blood thinners, medication choices are more important than ever. The new data makes a compelling case for doctors to carefully consider which antiseizure drugs are paired with anticoagulants, in hopes of reducing the very real risks of blood clots or bleeding.
