Acetylcysteine

What it is and how it works

Mechanism class: Reduction Activity

Indications

Acetylcysteine injection is indicated to prevent or lessen hepatic injury after ingestion of a potentially hepatotoxic quantity of acetaminophen in adults and pediatric patients who weigh 5 kg or greater with acute ingestion or from repeated supratherapeutic ingestion (RSI). Acetylcysteine injection is an antidote for acetaminophen overdose indicated to prevent or lessen hepatic injury after ingestion of a potentially hepatotoxic quantity of acetaminophen in adults and pediatric patients who weigh 5 kg or greater with an acute ingestion or from repeated supratherapeutic ingestion (RSI) .

Dosage and administration (summary)

Pre-Treatment Assessment Following Acute Ingestion : Prior to initiating treatment with Acetylcysteine injection, decide whether the three-bag or two-bag regimen will be used. Obtain a plasma or serum sample to assay for acetaminophen concentration at least 4 hours after ingestion. • If the time of acetaminophen ingestion is unknown: o Administer a loading dose of Acetylcysteine injection immediately. o Obtain an acetaminophen concentration to determine need for continued treatment.

Contraindications

Acetylcysteine injection is contraindicated in patients with a previous hypersensitivity reaction to acetylcysteine . Patients with a previous hypersensitivity reaction to acetylcysteine

Warnings and precautions

Hypersensitivity Reactions: Fatal or life-threatening anaphylaxis, rash, hypotension, wheezing, shortness of breath and/or bronchospasm have been observed. Observe patients during and after the infusion; immediately discontinue infusion if a serious reaction occurs and initiate appropriate treatment. Acetylcysteine injection infusion may be carefully restarted after treatment of hypersensitivity has been initiated and acute symptoms have resolved . Fluid Overload: Total volume administered should be reduced for patients weighing less than 40 kg and for those requiring fluid restriction .

Storage and supply

Acetylcysteine injection (acetylcysteine) injection is available as a 20% solution (200 mg/mL) in 30 mL single-dose glass vials. Each single dose vial contains 6 g/30mL (200 mg/mL) of Acetylcysteine injection. Acetylcysteine injection is sterile and can be used for intravenous administration.

Source: Acetylcysteine (Acetylcysteine) — US FDA prescribing information, 2025-09-12, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.