 Our central hypothesis is that through reductions in aquaporin-4 AQP4 expression, the early use of conivaptan will reduce CE while also being safe to the patient. Our long term goal is to show that early use of conivaptan in ICH will reduce CE. If this reduction is possible, we hypothesize improved outcome and reducing the need for rescue therapies, ICU length of stay, and overall treatment cost will follow. However, more data is needed to evaluate the dosing and amount of drug. With respect to conivaptans efficacy in correction of hyponatremia, a direct dose-response relationship exists. Further, this effect was more noted at milder degrees of hyponatremia. 