We have studied retrospectively the effects of dopamine in 31 hypotensive newborn infants four hours to twenty days of age, which did not improve with conventional therapy. Hypotension aetiology was in 23 septic, cardiogenic and hypovolemic shock, in 6 hemodynamic instability in patients with hyalin membrane disease (HMD), and in two patients after tolazoline treatment in neonatal persistent pulmonary hypertension. Arterial blood pressure significantly increased when doses 5 to 10 mg/kg/min dopamine were used. Diuresis significantly increased comparing 8 hours before and after dopamine infusion. Dopamine was considered to be clinically effective in similar rates in septic (47.6%) and cardiogenic shock (40%), in all cases of hypovolemic shock (after volume infusion) and in hypotension produced by tolazoline; in hypotensive newborn infants with HMD was effective in 83.3%. Tachycardia was present in five infants with high dose (17.4 +/- 8.4 mcg/kg/min.), it returned to normal value when dopamine was decreased or discontinued. Dopamine efficacy and its lack of severe secondary effects justifies its use in neonatal hypotension.