Intravenous N-Acetylcysteine (NAC) [Acetadote®]

for Acetaminophen Poisoning

1.IV NAC (Acetadote)

  1. Wholesaler acquisition cost for 4 vials (each 30 mL vial contains 6 g) is $416
  2. Manufactured by Cumberland Pharmaceuticals, Nashville, TN. 615-255-0068
  3. Indicated for prevention or treatment of acetaminophen toxicity
  4. Best if administered within 8 hours of ingestion, but never too late if indicated
  1. IV NAC (Acetadote): Adult Patient Dosing Regimen per Package Insert
  2. Loading Dose:
  3. 150 mg/kg in 200 mL of 5% dextrose in water (D5W) infused over 15 minutes
  4. First Maintenance Dose:
  5. 50 mg/kg in 500 mL of D5W infused over 4 hours
  6. Second Maintenance Dose:
  7. 100 mg/kg in 1000 mL of D5W over 16 hours
  1. IV NAC (Acetadote) Adult Patient: New York City Poison Control Protocol (dose identical to FDA approved dose)
  2. Mix 300 mg/kg (as correct volume of 20% NAC for patient weight) to make a total of 1000 mL with D5W
  3. For Example: For a 70 kg patient
  4. Remove the same volume (in this case 105 mL) from the 1000 mL D5W that will then need to be added
  5. Mix 105 mL of 20% NAC to remaining 895 mL D5W
  6. Loading dose: 500 mL over 60 min
  7. First maintenance infusion: 166 mL over 4 hours (40 mL/hour)
  8. Second maintenance infusion: 334 mL over 16 hours (21 mL/hour)
  1. IV NAC (Acetadote) Pediatric (< 40 kg) (Must monitor serum sodium every 6 hours)
  2. Dose same as adult, however the concentration (dilution) should be adjusted
  3. A 2% final concentration is acceptable
  4. Mix 50 mL of NAC (20% solution) with 450 mL of D5W (remove 50 mL from a 500 mL bag of D5W) to obtain 20 mg/mL (2%) concentration (485 mOsm/L)
  5. Loading dose: Infuse 7.5 mL/kg over 60 minutes
  6. First maintenance infusion: Infuse 2.5 mL/kg over 4 hours (0.63 mL/kg/hr)
  7. Second Maintenance infusion:Infuse 5 mL/kg over 16 hours (0.32 mL/kg/hr)
  8. IV NAC (Acetadote) for Dosing/Fluid Restricted Patients
  9. Dose same as adult, however the concentration (dilution) should be adjusted
  10. A 3% final concentration is acceptable
  11. Mix 75 mL of NAC (20% solution) with 425 mL of D5W (remove 75 mL from a 500 mL bag of D5W) to obtain 30 mg/mL (3%) concentration (620 mOsm/L)
  12. Loading dose: Infuse 5 mL/kg over 60 minutes
  13. First maintenance infusion: Infuse 1.7 mL/kg over 4 hours (0.425 mL/kg/hr)
  14. Second Maintenance infusion:Infuse 3.3 mL/kg over 16 hours (0.2 mL/kg/hr)
  15. NAC: Oral versus IV
  16. Choice of IV NAC (as Acetadote) or oral NAC?
  17. Consider oral therapy if asthmatic or prior anaphylactoid reaction
  18. IV to everyone else
  19. No direct comparison of the two regimens
  20. Comparable efficacy if administered < 8 hours
  21. Oral preparation has low bioavailability due to hepatic first pass elimination
  22. Oral preparation previously used IV but this is no longer routinely recommended

Table. IV (Acetadote) versus Oral NAC

IV / Oral
Duration of therapy / 20 hours / 72 hours
Anaphylactoid reactions / Possible / Rare
Effective in Fulminant hepatic failure / Proven / Not studied but likely
Comments / Assures delivery / Disagreeable taste & odor
Antiemetics often needed
  1. IV NAC (Acetadote): Adverse Reactions
  2. Estimates based on different studies
  3. Vasodilation, rash, pruritis about 2 to 10%
  4. Anaphylactoid reactions (N=109 patients; 15 min infusion)
  5. Mild: 6%
  6. Moderate 10%
  7. Severe 1%
  8. Caution advised in patients with asthma/bronchospasm
  9. Treatment of Adverse Reactions From IV NAC
  10. Flushing and erythema of skin alone, usually transient
  11. Diphenhydramine for urticaria & continue NAC
  12. Anaphylactoid reactions (above plus hypotension or SOB or wheezing)
  13. Stop NAC
  14. Administer diphenhydramine & standard symptomatic therapy including epinephrine if severe
  15. Carefully restart NAC after resolution
  16. If reaction persists or worsens D/C IV NACand consider risk benefit of oral NAC
  17. Continuation of IV NAC beyond 20 hours
  18. If APAP concentration at 20 hours > level of detection or LFT’s > 3X nl or rising
  19. If patient in fulminant hepatic failure (poor prognostic indicators)

Please call the New York CityPoisonControlCenter for more information

800-222-1222; 212-POISONS; 212-764-7667