N-Acetylcysteine Overdose After Acetaminophen Poisoning

N-acetylcysteine (NAC) is a drug  used  widely and effectively in oral  and  ‎intravenous  forms  as  a  specific  antidote  for acetaminophen poisoning.  In children ‎considering the toxic dose of acetaminophen ingested by the patient and the body weight, the ‎physician prescribes a specific dose of NAC. There is always a risk of  iatrogenic overdose of  ‎NAC  which can cause different mild to severe temporary or permanent  side effects, some of ‎which can be life threatening. Here we report a rare case of iatrogenic NAC overdose following ‎an error in calculation of the prescribed dose.‎The patient was a 2.5 years old boy that was brought to emergency room with overdose ‎of acetaminophen syrup. The Physician prescribed 2 grams of intravenous NAC for him, but ‎because of the miscalculation of the volume of the drug, the nurse infused about 20 grams of ‎NAC (10 times the prescribed dose) to the patient. Immediately the patient became drowsy and ‎developed decreased level of consciousness, stupor, repetitive intractable focal and generalized ‎convulsions, decrease visual acuity and had prolonged hospitalization in intensive care unit and ‎pediatric neurologic wards and perhaps will have permanent subtle intellectual and neurologic ‎sequela. Considering the possible errors in the prescription and administration of some ‎critical and less commonly used drugs especially those which have several different formulary ‎and also considering their possible serious and life threatening side effects, it is recommended ‎that the dose and volume of such medications be calculated meticulously by at least two trained ‎persons. Also it is important to carry out the administration phases and check the patient’s ‎symptoms more attentively and cautiously. ‎