Please check your internet connection and try again.
# Acetylcysteine
## Overview
Acetylcysteine is a mucolytic agent that breaks disulfide bonds in mucoproteins, reducing mucus viscosity. It is also an antidote for acetaminophen overdose by replenishing hepatic glutathione stores.
## Primary Indications
* Acetaminophen overdose
* Adjunct treatment of tracheobronchial secretions in conditions like bronchitis, COPD, and cystic fibrosis.
## Adult Dosing
* **Acetaminophen Overdose:**
* **Oral Loading Dose:** 140 mg/kg administered over 1 hour.
* **Oral Maintenance Doses:** 70 mg/kg every 4 hours for 17 doses.
* **Intravenous (IV) Loading Dose:** 150 mg/kg IV over 1 hour.
* **IV Maintenance Doses:** 50 mg/kg IV over 4 hours, followed by 100 mg/kg IV over 16 hours. Total treatment duration is 21 hours.
* *Note:* IV dosing may be adjusted based on acetaminophen levels and time since ingestion. Local protocols should be followed. Maximum IV infusion rate should not exceed 15 mg/kg/hour.
* **Mucolytic Therapy:**
* **Nebulization:** 10% solution: 3-5 mL every 3-4 hours as needed. 20% solution: 1.5-3 mL every 3-4 hours as needed.
* **Direct Instillation:** 10% solution: 1-2 mL every 1-2 hours into tracheostomy or endotracheal tube.
## Pediatric Dosing
* **Acetaminophen Overdose:** Dosing is the same as adult dosing based on weight.
* **Mucolytic Therapy:** Dosing is the same as adult dosing based on concentration and volume.
## Dose Adjustments
No specific dose adjustments are typically required for renal or hepatic impairment for mucolytic indications. For acetaminophen overdose, IV dosing may need adjustment based on serum acetaminophen levels and time since ingestion, following established nomograms and local protocols.
## Contraindications
Hypersensitivity to acetylcysteine.
## Adverse Effects
* **Nebulized:** Bronchospasm, nausea, vomiting, stomatitis, rhinorrhea.
* **IV (for overdose):** Anaphylactoid reactions (rash, urticaria, angioedema, bronchospasm, dyspnea, hypotension), flushing, fever.
## Key Drug Interactions
* **Activated Charcoal:** May adsorb oral acetylcysteine, reducing its efficacy. Separate administration by at least 1 hour.
* **Nitroglycerin:** Potential for additive hypotensive effects. Monitor blood pressure.
## Monitoring
* **Acetaminophen Overdose:** Serum acetaminophen levels, liver function tests (AST, ALT, bilirubin, INR), renal function, glucose, and electrolytes. Monitor for signs of anaphylactoid reaction during IV infusion.
* **Mucolytic Therapy:** Assess for improvement in airway clearance and reduction in mucus viscosity. Monitor for bronchospasm.
## Clinical Pearls
* The odor of acetylcysteine can be unpleasant; this is normal.
* For nebulized acetylcysteine, concurrent administration with a bronchodilator (e.g., albuterol) may be necessary to prevent or treat bronchospasm, especially in patients with reactive airway disease.
* IV acetylcysteine for acetaminophen overdose is generally preferred over oral due to better palatability and absorption, and reduced risk of emesis.
* Prompt initiation of acetylcysteine therapy is crucial for optimal outcomes in acetaminophen overdose.
***
*This information is intended for healthcare professionals. Always consult the most current prescribing information and relevant clinical guidelines before making any treatment decisions.*
