Lorazepam metabolic acidosis with

A 34-year-old woman with a history of renal insufficiency induced by long-term use of cocaine developed respiratory failure and was intubated and sedated with intravenous lorazepam (65 mg, 313 mg, and 305 mg on 3 consecutive days). After 2 days she had a metabolic acidosis, with hyperlactatemia and hyperosmolality. Propylene glycol, a component of the lorazepam intravenous formulation, was considered as a potential source of the acidosis, as she had received more than 40 times the recommended amount over 72 hours. Withdrawal of lorazepam produced major improvements in lactic acid and serum osmolality. 

Refractory GCSE has also been treated with large-dose continuous infusion lorazepam or diazepam. Lorazepam contains propylene glycol, which can accumulate and cause marked osmolar gap, metabolic acidosis, and renal toxicity. 

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