N-Acetylcysteine: Difference between revisions

No edit summary
No edit summary
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*Type:  
*Type:  
*Dosage Forms:
*Dosage Forms:
*Common Trade Names:  
*Common Trade Names: NAC;


==Adult Dosing==
==Adult Dosing==
===[[Acetaminophen (tylenol) toxicity]]===
====PO====
#140mg/kg PO load
#70mg/kg PO q4hr x17 doses additional; dilute to 5% soln
====IV====
#Loading dose: 150mg/kg in 100 mL D5W over 60min
#Second (maintenance) dose: 50mg/kg in 250 mL D5W over 4hr
#Third dose: 100mg/kg in 500 mL D5W over 16hr
====Comments====
#Almost 100% effective if given <8 hr post-ingestion; less effective if 16-24 hr post-ingestion
#May still be useful >24 hr post-ingestion, even with fulminant hepatic failure. Give NAC until LFTs improve (not until APAP level is 0) <ref>Keays R, Harrison PM, Wendon JA, et al. Intravenous acetylcysteine in paracetamol-induced fulminant hepatic failure: a prospective controlled trial. BMJ. 1991;303(6809):1026-1029. (Prospective randomized controlled trial; 50 patients)</ref> <ref>Harrison PM, Keays R, Bray GP, et al. Improved outcome of paracetamol-induced fulminant hepatic failure by late administration of N-acetylcysteine. Lancet. 1990;335(8705):1572- 1573. (Retrospective analysis; 100 patients)</ref>
#Be aware NAC treatment may affect PT. May see a dose-dependent increase in PT following NAC in patients without hepatotoxicity. <ref>Wasserman GS, Garg U. Intravenous administration of Nacetylcysteine: interference with coagulopathy testing. Ann Emerg Med. 2004;44(5):546-547. (Letter)</ref>


==Pediatric Dosing==
==Pediatric Dosing==
Line 10: Line 24:
==Special Populations==
==Special Populations==
*[[Drug Ratings in Pregnancy|Pregnancy Rating]]:
*[[Drug Ratings in Pregnancy|Pregnancy Rating]]:
{{NAC use in pregnancy}}
*Lactation:
*Lactation:
*Renal Dosing
*Renal Dosing
Line 22: Line 38:


==Adverse Reactions==
==Adverse Reactions==
===Serious===
*sulfur-smell causes nausea and vomiting. Consider mixing with juice or soda, in a cup with a lid and straw
 
*Anaphylactoid reaction but also associated with seizures, cerebral edema, & herniation. <ref>http://journals.lww.com/em-news/Fulltext/2012/02000/Toxicology_Rounds__Lessons_from_the_Courtroom_.9.aspx</ref>
===Common===
*Anaphylaxis responds to standard therapies and can usually restart NAC without safely without complications.  <ref>Sandilands EA, Bateman DN. Adverse reactions associated with acetylcysteine. Clin Toxicol (Phila). 2009;47(2):81-88. (Systematic literature review)</ref>


==Pharmacology==
==Pharmacology==
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*Excretion:  
*Excretion:  
*Mechanism of Action:
*Mechanism of Action:
**Intravenous acetylcysteine is indicated for the treatment of acetaminophen overdose by preventing depletion of glutathione reserves.


==See Also==
==See Also==
*[[Acetaminophen (tylenol) toxicity]]


==Sources==
==Sources==


<references/>
<references/>
[[Category:Drugs]]
*Also known as NAC
*Intravenous acetylcysteine is indicated for the treatment of acetaminophen overdose by preventing depletion of glutathione reserves.
{{NAC use in pregnancy}}
==N-acetylcysteine (NAC)==
===Background===
#Almost 100% effective if given <8 hr post-ingestion; less effective if 16-24 hr post-ingestion
#May still be useful >24 hr post-ingestion, even with fulminant hepatic failure. Give NAC until LFTs improve (not until APAP level is 0) <ref>Keays R, Harrison PM, Wendon JA, et al. Intravenous acetylcysteine in paracetamol-induced fulminant hepatic failure: a prospective controlled trial. BMJ. 1991;303(6809):1026-1029. (Prospective randomized controlled trial; 50 patients)</ref> <ref>Harrison PM, Keays R, Bray GP, et al. Improved outcome of paracetamol-induced fulminant hepatic failure by late administration of N-acetylcysteine. Lancet. 1990;335(8705):1572- 1573. (Retrospective analysis; 100 patients)</ref>
#Be aware NAC treatment may affect PT. May see a dose-dependent increase in PT following NAC in patients without hepatotoxicity. <ref>Wasserman GS, Garg U. Intravenous administration of Nacetylcysteine: interference with coagulopathy testing. Ann Emerg Med. 2004;44(5):546-547. (Letter)</ref>
===Dosing:===
====PO====
#140mg/kg PO load
#70mg/kg PO q4hr x17 doses additional; dilute to 5% soln
;Side Effects: sulfur-smell causes nausea and vomiting. Consider mixing with juice or soda, in a cup with a lid and straw
====IV====
#Loading dose: 150mg/kg in 100 mL D5W over 60min
#Second (maintenance) dose: 50mg/kg in 250 mL D5W over 4hr
#Third dose: 100mg/kg in 500 mL D5W over 16hr
;Side Effects:
#Anaphylactoid reaction but also associated with seizures, cerebral edema, & herniation. <ref>http://journals.lww.com/em-news/Fulltext/2012/02000/Toxicology_Rounds__Lessons_from_the_Courtroom_.9.aspx</ref>
#Anaphylaxis responds to standard therapies and can usually restart NAC without safely without complications.  <ref>Sandilands EA, Bateman DN. Adverse reactions associated with acetylcysteine. Clin Toxicol (Phila). 2009;47(2):81-88. (Systematic literature review)</ref>
==See Also==
*[[Acetaminophen (Tylenol) Toxicity]]
[[Category:Drugs]]
[[Category:Drugs]]

Revision as of 20:07, 28 January 2015

General

  • Type:
  • Dosage Forms:
  • Common Trade Names: NAC;

Adult Dosing

Acetaminophen (tylenol) toxicity

PO

  1. 140mg/kg PO load
  2. 70mg/kg PO q4hr x17 doses additional; dilute to 5% soln

IV

  1. Loading dose: 150mg/kg in 100 mL D5W over 60min
  2. Second (maintenance) dose: 50mg/kg in 250 mL D5W over 4hr
  3. Third dose: 100mg/kg in 500 mL D5W over 16hr

Comments

  1. Almost 100% effective if given <8 hr post-ingestion; less effective if 16-24 hr post-ingestion
  2. May still be useful >24 hr post-ingestion, even with fulminant hepatic failure. Give NAC until LFTs improve (not until APAP level is 0) [1] [2]
  3. Be aware NAC treatment may affect PT. May see a dose-dependent increase in PT following NAC in patients without hepatotoxicity. [3]

Pediatric Dosing

Special Populations

  • Pregnancy Rating:
  • Both IV or oral NAC may be used in pregnant patients with Acetaminophen toxicity. [4]
    • IV formulation may be preferred to increase fetal NAC concentrations
  • Lactation:
  • Renal Dosing
    • Adult
    • Pediatric
  • Hepatic Dosing
    • Adult
    • Pediatric

Contraindications

  • Allergy to class/drug

Adverse Reactions

  • sulfur-smell causes nausea and vomiting. Consider mixing with juice or soda, in a cup with a lid and straw
  • Anaphylactoid reaction but also associated with seizures, cerebral edema, & herniation. [5]
  • Anaphylaxis responds to standard therapies and can usually restart NAC without safely without complications. [6]

Pharmacology

  • Half-life:
  • Metabolism:
  • Excretion:
  • Mechanism of Action:
    • Intravenous acetylcysteine is indicated for the treatment of acetaminophen overdose by preventing depletion of glutathione reserves.

See Also

Sources

  1. Keays R, Harrison PM, Wendon JA, et al. Intravenous acetylcysteine in paracetamol-induced fulminant hepatic failure: a prospective controlled trial. BMJ. 1991;303(6809):1026-1029. (Prospective randomized controlled trial; 50 patients)
  2. Harrison PM, Keays R, Bray GP, et al. Improved outcome of paracetamol-induced fulminant hepatic failure by late administration of N-acetylcysteine. Lancet. 1990;335(8705):1572- 1573. (Retrospective analysis; 100 patients)
  3. Wasserman GS, Garg U. Intravenous administration of Nacetylcysteine: interference with coagulopathy testing. Ann Emerg Med. 2004;44(5):546-547. (Letter)
  4. Heard KJ. Acetylcysteine for acetaminophen poisoning. N Eng J Med. 2008;359(3):285-292. (Review)
  5. http://journals.lww.com/em-news/Fulltext/2012/02000/Toxicology_Rounds__Lessons_from_the_Courtroom_.9.aspx
  6. Sandilands EA, Bateman DN. Adverse reactions associated with acetylcysteine. Clin Toxicol (Phila). 2009;47(2):81-88. (Systematic literature review)