Parenteral Manual


Disclaimer: Official controlled document is the CHEO online copy. It is the responsibility of user to ensure that any paper copy version is the same as the online version before use.

Alternate Name(s): 
MUCOMYST®, PARVOLEX®, N-Acetylcysteine
Antidote for acetaminophen poisoning
Original Date: 
August 2005
Revised Date: 
June 2019
  • Antidote to prevent or minimize hepatic injury following a potentially toxic acetaminophen ingestion
  • Mucolytic agent
  • Prevention of contrast media-induced nephropathy
Reconstitution and Stability: 
  • Store at room temperature
  • Available as a 20% solution = 200 mg/mL
  • Vial is stable 96 hours refrigerated once punctured
  • Solutions diluted for bladder irrigation stable 28 days refrigerated (0.001% - 6 % or 0.01 mg/mL - 60 mg/mL) or 14 days at room temperature

- Solutions Compatible:  D5W, 0.9% NaCl

- Additives/Above Cassette Compatible:  no information

- Y-site Compatible:  no information

- Incompatible: amphotericin B, tetracyclines, erythromycin, ampicillin


(For approved routes of administration by nursing personnel, refer to Policy for the Administration of Intravenous Medications.)

IV Direct NO
IV Intermittent Infusion YES
IV Continuous Infusion YES
Large volume pump:  usual dilution 30 mg/mL





(For neonatal dosages, refer to Neonatal IV Drug Manual.)

Adults and Pediatric:

- Acetaminophen Poisoning


  • Loading Dose:  60 mg/kg/hr (MAX 6 g/hr) IV x 4 hours followed by
  • Maintenance Infusion:  6 mg/kg/hr (MAX 600 mg/hr) IV continuously until advised to stop by Ontario Poison Centre


  • Loading Dose:  60 mg/kg/hr (MAX 6 g/hr)  IV x 4 hour followed by
  • Maintenance Infusion:  12 mg/kg/hr (MAX 1200 mg/hr) IV continuously until advised to stop by Ontario Poison Centre


- Prevention of contrast media-induced nephropathy

      - 25 - 50 mg/kg IV 30 min prior to contrast and Q8H x 3 doses

Potential hazards of parenteral administration: 

Hypersensitivity reactions have been reported:  rash, urticaria, facial edema, hypotension/hypertension, tachycardia, bronchospasm, anaphylaxis

  • Nausea, vomiting, flushing
  • Therapy is most effective when administered within the first 8-10 hours post acetaminophen ingestion
  • IV dose is NOT the same as the oral dose; IV therapy preferable if patient vomiting, or if activated charcoal or syrup of Ipecac have been used
  • Monitor acetaminophen level and liver function tests
  • Consultation with the Ontario Poison Control Center may be required to individualize the treatment.  (416-813-5900)

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