AHFS Class:

91:04.04 Acetaminophen antidote

Generic Name

• Acetylcysteine

Acetylcysteine is available as a 20% (200 mg/mL) concentrate for injection in 30-mL single-dose preservative-free vials containing 6 g of the drug.²⁸⁶¹ Each mL of the concentrate contains acetylcysteine 200 mg in water for injection with sodium hydroxide to adjust the pH.²⁸⁶¹ The concentrate must be diluted prior to administration.²⁸⁶¹ Dextrose 5%, sodium chloride 0.45%, or sterile water for injection may be used; the manufacturer states that, in general, sodium chloride 0.45% is the preferred diluent because it provides a more consistent osmolarity profile, reduces the amount of free water delivered to the patient, and better approximates physiologic fluids than dextrose 5% or sterile water for injection.²⁸⁶¹ Dextrose 5% or sterile water for injection may be considered if sodium load is a concern.²⁸⁶¹

pH

6 to 7.5.²⁸⁶¹

Osmolarity

Acetylcysteine concentrate for injection has an osmolarity of 2600 mOsm/L.²⁸⁶¹ The manufacturer provides the osmolarity of acetylcysteine solutions for the following dilutions:²⁸⁶¹

The osmolarity of acetylcysteine solutions was calculated for the following dilutions:³⁸⁸⁶

Trade Name(s)

Acetadote

Acetylcysteine is administered by intravenous infusion after dilution in dextrose 5%, sodium chloride 0.45%, or sterile water for injection.²⁸⁶¹ The total recommended dose is administered as either a 3-bag regimen or a 2-bag regimen.²⁸⁶¹ The 3-bag regimen is administered as 3 sequential intravenous infusions (loading dose, second dose, and third dose) over a total of 21 hours.²⁸⁶¹ The 2-bag regimen is administered as 2 sequential intravenous infusions (loading dose and second dose) over a total of 20 hours.²⁸⁶¹ The total volume of the infusions will vary based on the patient's weight and dosage regimen (i.e., 3-bag or 2-bag).²⁸⁶¹ The total volume of the infusions should be adjusted for patients weighing 40 kg or less and those requiring fluid restriction.²⁸⁶¹

3-bag regimen (patients weighing 5 kg or greater):

In the 3-bag regimen, the loading dose (Bag 1) is infused over 1 hour, followed by the second dose (Bag 2) infused over 4 hours, and the third dose (Bag 3) infused over 16 hours.²⁸⁶¹ The volumes of diluent recommended are as follows:

Patients weighing 5 to 20 kg: The manufacturer recommends the loading dose (Bag 1) be diluted in 3 mL/kg of body weight, the second dose (Bag 2) diluted in 7 mL/kg of body weight, and the third dose (Bag 3) diluted in 14 mL/kg of body weight.²⁸⁶¹

Patients weighing 21 to 40 kg: The manufacturer recommends the loading dose (Bag 1) be diluted in 100 mL, the second dose (Bag 2) diluted in 250 mL, and the third dose (Bag 3) diluted in 500 mL.²⁸⁶¹

Patients weighing 41 kg or greater: The manufacturer recommends the loading dose (Bag 1) be diluted in 200 mL, the second dose (Bag 2) diluted in 500 mL, and the third dose (Bag 3) diluted in 1000 mL.²⁸⁶¹

2-bag regimen (patients weighing at least 41 kg):

In the 2-bag regimen, the loading dose (Bag 1) is infused over 4 hours followed by the second dose (Bag 2) infused over 16 hours.²⁸⁶¹ The volumes of diluent recommended are as follows:

Patients weighing 41 kg or greater: The manufacturer recommends the loading dose (Bag 1) be diluted in 1000 mL and the second dose (Bag 2) in 500 mL.²⁸⁶¹

Intact vials of acetylcysteine should be stored at controlled room temperature.²⁸⁶¹ The vials are for single use; any unused portion remaining in vials should be discarded.²⁸⁶¹ The manufacturer states that the color of acetylcysteine injection may vary from colorless to slight pink or purple after stopper penetration, but this color change does not indicate an adverse effect on drug quality.²⁸⁶¹

The manufacturer states diluted solutions may be stored for 24 hours at room temperature.²⁸⁶¹

Solution Compatibility

Y-Site Injection Compatibility (1:1 Mixture)

For a list of references cited in the text of this monograph, search the monograph titled References.

ASHP^® Injectable Drug Information^TM. Selected Revisions March 7, 2025. © Copyright, 2025. American Society of Health-System Pharmacists^®, 4500 East-West Highway, Suite 900, Bethesda, Maryland 20814.