A 40 year old male was found unresponsive in the garden. Initial GCS was 9 (E3V2M4) which deteriorated to 7 (E2V2M3) on arrival to the emergency department. ECG and CT brain were both normal. An ABG demonstrated a high anion gap metabolic acidosis (pH 7.0) with an increased osmolal gap (>10mOsm/kg). In view of unexplained decreased level of consciousness along with high anion gap acidosis and high osmolal gap, ethylene glycol toxicity was considered to be the most likely diagnosis.