Please check your internet connection and try again.
# Acetylcysteine
## Overview
Acetylcysteine is a mucolytic agent that breaks down disulfide bonds in mucoproteins, reducing the viscosity of mucus. It also acts as an antidote to acetaminophen overdose by replenishing hepatic glutathione stores.
## Primary Indications
* **Acetaminophen Overdose:** To prevent or reduce the severity of liver damage.
* **Mucolytic:** To thin mucus in conditions such as cystic fibrosis, chronic bronchitis, and pneumonia.
## Adult Dosing
**Acetaminophen Overdose:**
* **Oral Loading Dose:** 140 mg/kg as a single dose.
* **Oral Maintenance Doses:** 70 mg/kg every 4 hours for 17 additional doses (total of 18 doses).
* **Intravenous (IV) Loading Dose:** 150 mg/kg infused over 1 hour.
* **IV Maintenance Doses:** 50 mg/kg infused over 4 hours, followed by 100 mg/kg infused over 16 hours. (Total IV infusion time is 21 hours).
**Mucolytic (Nebulized):**
* 3-5 mL of a 20% solution or 6-10 mL of a 10% solution every 2-6 hours as needed.
## Pediatric Dosing
**Acetaminophen Overdose:**
* Dosing is the same as adult dosing (140 mg/kg oral loading dose, followed by 70 mg/kg oral maintenance doses or IV equivalent).
**Mucolytic (Nebulized):**
* **For infants and children:** 1-2 mL of a 20% solution or 2-4 mL of a 10% solution every 2-6 hours as needed.
## Dose Adjustments
No dose adjustments are typically required for hepatic or renal impairment, as acetylcysteine is metabolized systemically.
## Contraindications
Hypersensitivity to acetylcysteine.
## Adverse Effects
* **Nebulized:** Bronchospasm, rhinorrhea, nausea, vomiting, stomatitis.
* **Oral:** Nausea, vomiting, diarrhea.
* **IV:** Anaphylactoid reactions (rash, pruritus, urticaria, angioedema, bronchospasm, dyspnea, hypotension), fever, tachycardia.
## Key Drug Interactions
* **Activated Charcoal:** May bind to oral acetylcysteine, reducing its absorption. If both are used, administer charcoal at least 1 hour after acetylcysteine.
* **Nitroglycerin:** May potentiate the vasodilatory effects, leading to hypotension and headache.
## Monitoring
* **Acetaminophen Overdose:**
* Serum acetaminophen levels.
* Liver function tests (AST, ALT, bilirubin, INR).
* Renal function and electrolytes.
* Prothrombin time.
* **Mucolytic:**
* Respiratory status, effectiveness in thinning mucus.
## Clinical Pearls
* The effectiveness of acetylcysteine in acetaminophen overdose is time-dependent; it is most effective when initiated within 8-10 hours of ingestion.
* For IV administration in acetaminophen overdose, close monitoring for anaphylactoid reactions is crucial. Pretreatment with antihistamines may be considered.
* Nebulized acetylcysteine has an unpleasant sulfurous odor.
* Dilute nebulized acetylcysteine with sterile water or saline if necessary for patient comfort.
***
*This information is intended for clinical use and does not substitute for professional medical advice. Always verify current prescribing information with the manufacturer's official product labeling or other authoritative sources.*
