Nesiritide is a human B-type natriuretic peptide (BNP) produced by recombinant technology having the same amino acid sequence as the naturally occurring human BNP. BNP is predominantly secreted by the cardiac ventricles in response to increased cardiac volume and pressure overload. Its pharmacologic effects include hemodynamic, neurohormonal, and renal. In adult studies, hemodynamic effects are characterized by balanced venous and arterial dilation, resulting in decreased preload and afterload demonstrated by a reduction of pulmonary capillary wedge pressure, pulmonary arterial pressure, and systemic vascular resistance while neurohormonal effects of nesiritide favorably inhibit the renin-angiotension-aldosterone system, leading to decreased plasma aldosterone and norepinephrine levels. The renal effects most often seen with nesiritide use is increased urine output and lower diuretic utilization.