Ethylene glycol, a common component in automotive antifreeze and various household and industrial products, poses significant health risks upon ingestion, whether accidental or intentional. Characterized by severe metabolic acidosis, calcium oxalate crystal formation, and diverse end-organ damage, ethylene glycol toxicity can be fatal, with a potentially lethal dose estimated at 1500 mg/kg. The parent compound is osmotically active, leading to the production of harmful metabolites, such as glycolic and oxalic acids, which contribute to metabolic acidosis, nephrotoxicity, and cardiac toxicity. Acute management strategies involve supportive care, administration of fomepizole as a competitive enzyme inhibitor, and renal elimination through dialysis. Furthermore, the lactate gap serves as an important diagnostic tool in ethylene glycol poisoning, highlighting discrepancies between measured and expected lactate levels, which can indicate metabolic acidosis and tissue hypoperfusion. We present a case of ethylene glycol poisoning complicated by cardiac arrest in spite of initiating treatment and the possible use of the lactate gap to predict severity.