Importance: Hypertension and carotid stenosis are both risk factors for stroke, but the presence of carotid stenosis might dampen enthusiasm for tight control of hypertension because of concerns for hypoperfusion. Objective: To determine the extent to which there are opportunities to potentially improve pharmacotherapy for hypertension in patients known to have asymptomatic high-grade carotid stenosis. Design: We examined anti-hypertensive medication prescription and adherence to evidence-based hypertension treatment guidelines in a cross-sectional analysis of baseline data of patients enrolled in a clinical trial. Setting: The Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial (CREST-2) is a multicenter prospective randomized open blinded end-point clinical trial of intensive medical management with or without revascularization by endarterectomy or stenting for asymptomatic high-grade carotid stenosis. Participants: 1479 participants (38.6% female; mean age 69.8 years) from 132 clinical centers enrolled in the CREST-2 trial as of April 6, 2020 who were taking >1 antihypertensive drug at baseline. Exposures: Pharmacotherapy for hypertension. Main outcome: Adherence to evidence based guidelines for treating hypertension. Results: Of 1458 participants with complete data, 26% were on one, 31% on 2, and 43% on >3 antihypertensive medications at trial entry. Thirty-two percent of participants were prescribed thiazide; 74%, angiotensin converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB); 38%, calcium channel blocker (CCB); 56%, a beta blocker; 11%, loop diuretic; and 27%, other. Of those prescribed a single antihypertensive medication, the proportion prescribed thiazide was 5%; ACEI or ARB, 55%, and CCB, 11%. The prevalence of guideline-adherent regimens was 34% (95% CI, 31-36%). Conclusions and relevance: In a diverse cohort with severe carotid disease and hypertension, non-adherence to hypertension guidelines was common. All preferred classes of antihypertensive drug were under-prescribed. Using staged iterative guideline-based care for hypertension, CREST-2 will characterize drug tolerance and stroke rates under these conditions. Trial registration: ClinicalTrials.gov Number NCT02089217.& nbsp; & nbsp;(c) 2021 Elsevier Inc. All rights reserved.