Antithrombotic medications increase the risk of subdural hematoma, with vitamin K antagonists (VKAs) such as warfarin producing the highest risk. Researchers from Denmark performed a case-control study of more than 10,000 patients presenting with first-ever subdural hematoma from 2000-2015 matched to more than 400,000 individuals from the general population. The drugs compared included low-dose aspirin, clopidogrel, VKAs, direct oral anticoagulants (dabigatran, rivaroxaban, or apixaban), or combinations of drugs. Almost 50% of patients with subdural hematoma were taking one of these medications. The odds ratios for subdural hematoma were: low-dose aspirin, 1.24; clopidogrel, 1.87; a direct oral anticoagulant, 1.73; and VKA, 3.69. The risk was highest when patients were on an antiplatelet drug along with a VKA. The odds ratio for VKA plus low-dose aspirin was 4.00 and VKA plus clopidogrel, 7.93. The authors noted that antithrombotic use increased during the 15-year study period. They concluded that antithrombotic drug use was associated with higher risk of subdural hematoma, and the highest odds of subdural hematoma was associated with combined use of a VKA and an antiplatelet drug (JAMA 2017;317:836-846). This study suggests that the newer direct oral anticoagulants may be safer in this regard than warfarin therapy.