BACKGROUND: Intravenous antihypertensives are frequently used to control blood pressure after successful endovascular thrombectomy (EVT), yet studies investigating the relationship between intravenous antihypertensive use and functional outcomes after successful EVT remain limited. METHODS: We conducted an exploratory secondary analysis of the OPTIMAL-BP trial (Outcome in Patients Treated With Intra-Arterial Thrombectomy–Optimal Blood Pressure Control), which compared intensive (systolic blood pressure <140 mm Hg) versus conventional blood pressure management (systolic blood pressure, 140–180 mm Hg) within the first 24 hours after successful recanalization across 19 stroke centers in South Korea between June 2020 and November 2022. Patients were classified according to the administration of intravenous antihypertensives within the initial 24 hours after enrollment. The primary efficacy outcome was functional independence (modified Rankin Scale score of 0–2) at 3 months. RESULTS: Of the 302 patients (median, 75 years; 180 [59.6%] men), 141 (46.7%) received intravenous antihypertensives within the first 24 hours after EVT. Among the 141 patients who received intravenous antihypertensives, 133 (94.3%) were treated with nicardipine, 10 (7.0%) received labetalol, and 2 (1.4%) were administered both drugs. Patients who received intravenous antihypertensives had significantly lower rates of functional independence at 3 months (adjusted odds ratio, 0.51 [95% CI, 0.27–0.95]; P =0.035) and excellent neurological recovery at 24 hours (adjusted odds ratio, 0.46 [95% CI, 0.22–0.94]; P =0.036), as well as higher stroke-related mortality rates (adjusted odds ratio, 4.21 [95% CI, 1.24–16.4]; P =0.027), compared with patients who did not receive intravenous antihypertensives. Symptomatic intracerebral hemorrhage was not significantly different between groups (adjusted odds ratio, 1.67 [95% CI, 0.68–4.19]; P =0.267). CONCLUSIONS: The use of intravenous antihypertensives within the first 24 hours after successful EVT was associated with worse functional outcomes at 3 months. This finding highlights the need for a cautious assessment of the risks and benefits of administering intravenous antihypertensives immediately after EVT. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04205305.