Background: Therapeutic hypothermia provides up to 30% neuroprotection in moderate to severe hypoxic ischemic encephalopathy (HIE). Additional neuroprotection may be achieved by using concomitant pharmacologic neuroprotective agents. Aim: The aim was to evaluate the safety of concomitant neuroprotective therapy of therapeutic hypothermia and magnesium sulfate (MgSO 4) in the management of moderate and severe HIE in term and near-term infants. Study Design: Multicenter double-blind randomized controlled trial. Methodology: Term and near-term newborn infants (≥35 weeks) with a clinical diagnosis of moderate or severe HIE were randomized to either Arm A (therapeutic hypothermia plus MgSO 4) or Arm B (therapeutic hypothermia plus placebo) using a net-based randomization system. Both groups received, within 6 h of birth, standard hypothermia therapy (72 h of cooling to 33.5°C followed by slow rewarming over a period of 8 h) plus either MgSO 4 (250 mg/kg/dose ×3 doses) or placebo (normal saline). The groups were compared for short-term predischarge adverse outcomes. Results: A total of 60 patients were randomized (29 in Arm A and 31 in Arm B). Both groups had similar baseline characteristics (P > 0.05) including severity of HIE. There were no differences in the short-term adverse outcomes (death, seizures, thrombocytopenia, coagulopathy, renal failure, elevated liver function test's, hypotension, intracranial hemorrhage, necrotizing enterocolitis, pulmonary hemorrhage, persistent pulmonary hypertension, and pulmonary air leak syndromes) between the two groups (P > 0.05). Conclusions: The combined use of therapeutic hypothermia and MgSO 4 appears to be safe particularly with respect to maintaining normal blood pressure and coagulopathy. Long-term survival and neurodevelopmental outcomes remain to be evaluated.