The goal of the study was to evaluate the effect of isoproterenol prescribed in goal-directed therapy for septic shock. Out of a cohort of 89 patients with septic shock, 14 patients treated with fluid and norepinephrine had inappropriate mixed venous oxygen saturation (S v O 2< 70%) not responding to correction of hypoxemia and anemia (> 8 g· dL− 1). Isoproterenol administration was started at a dose of 0.04 μg· kg− 1· minute− 1 with 0.025 μg· kg− 1· minute− 1 increments every 30 minutes until S v O 2 was greater than 70%. Mean arterial pressure was maintained≥ 65 mm· Hg by adjusting the norepinephrine infusion. Hemodynamic, oxygen, and renal variables were collected during a 12-h period. Patients with a known prior history of coronary disease were not eligible. Isoproterenol administration increased significantly S v O 2 (62%±10% to 71%±9%), cardiac index (3.1±0.6 to 4.4±1.4 L· min− 1· m− 2), stroke index (27±3.4 to 38±6.1 mL· m− 2), and left ventricular stroke work index (24±3.4 to 40±5.0 g· m− 1· m− 2). Heart rate rise did not reach a significant level. Arterial lactate concentration decreased significantly during the study period (5.7±2.8 to 3.4±1.6 mmol· L− 1). No cardiac adverse events occurred with any electrocardiographic aspects of myocardial ischemia. This study suggests that isoproterenol is efficient to improve hemodynamics and oxygen variables in septic shock patients. There is a need for future investigations in larger groups of patients to determine whether isoproterenol can be an alternative to dobutamine.