Q: Out of following which drug's IV infusion in ICU does not pose threat of propylene glycol toxicity?

A) Lorazepam 
B) Diazepam
C) Midazolam


Answer:  C

Propylene glycol is the solvent used as a carrier to deliver intravenous lorazepam or diazepam infusion. Threat of high an-ion gap metabolic acidosis is always potential on patients with long term or high dose infusions. Midazolam does not require propylene glycol  as a carrier.


References:

1. Wilson KC, Reardon C, Theodore AC, Farber HW. Propylene glycol toxicity: a severe iatrogenic illness in ICU patients receiving IV benzodiazepines: a case series and prospective, observational pilot study. Chest 2005; 128:1674. 

2. Wilson KC, Reardon C, Farber HW. Propylene glycol toxicity in a patient receiving intravenous diazepam. N Engl J Med 2000; 343:815.