Background/Aims: Endovascular recanalization therapies are an increasingly used strategy for acute cerebral ischemia with heterogeneous clinical outcomes. We aimed to determine the impact of previous medication on ischemic stroke following intra-arterial revascularization therapy. Methods: Consecutive patients receiving intra-arterial reperfusion therapy after an acute intracranial occlusion were analyzed. Premorbid use of antiplatelets, statins, oral antidiabetic drugs, antihypertensive drugs and oral anticoagulants were recorded. Collateral pial circulation (CPC) was scored on initial angiogram. Results: 118 patients were included (mean age 70.4 ± 11 years, 45% female). 66 patients (56%) were cardioembolic, 30 (25%) atherothrombotic, and 22 (19%) other/unknown etiologies. No significant impact of medication was detected in all the series or cardioembolic strokes. However, relevant differences were found among atherothrombotic strokes. The previous use of antiplatelets was associated with smaller infarct volume (64 vs. 170 ml; p = 0.043) whereas premorbid statin predicted reduced infarct volume (64 vs. 215 ml; p = 0.019), clinical improvement (79 vs. 29%; p = 0.016) and good CPC (100 vs. 20%; p = 0.04). Statins were the only medication independently predicting reduced infarct volume and clinical improvement and this effect depended on CPC. Conclusion: Previous use of statins may preferentially benefit patients with atherothrombotic strokes by favoring the development of CPC.