 Over 60 of AIS patients present with a transient acute hypertensive response, which is theorized to be the result of either increased sympathoadrenal tone, poorly controlled underlying hypertension, or an unknown stroke-specific mechanism related to augmenting cerebral perfusion through collateral blood flow. Epidemiological data suggests worse stroke outcomes are associated with extremes of sustained hypo- or hypertension, which has led to dozens of clinical trials involving over 20,000 patients to determine if pharmacologically lowering blood pressure after AIS is beneficial. The results have been persistently neutral or negative. In contrast, there have been no major clinical trials on the efficacy of using vasopressor medications to maintain or increase baseline blood pressure after AIS, despite promising preclinical data and pilot studies that showed no increase in cerebral hemorrhage or edema. The only randomized trial of vasopressor use after AIS demonstrated an improvement in clinical outcomes, but there was no difference in mean blood pressure between the control and intervention arms, suggesting the beneficial effect was not exclusively related to induced hypertension. One possibility is that the vasopressor reduced blood pressure variability, which preliminary data has shown to be detrimental after AIS, although that aspect of neurovascular coupling has not been adequately studied in the acute phase after AIS. 