Please check your internet connection and try again.
# Acetylcysteine
## Overview
Acetylcysteine is a mucolytic agent that breaks disulfide bonds in mucoproteins, decreasing mucus viscosity. It also acts as an antidote for acetaminophen overdose by replenishing glutathione stores.
## Primary Indications
* Acetaminophen overdose
* Adjunct to systemic hydration in patients with conditions associated with thickened bronchial secretions (e.g., bronchitis, emphysema, cystic fibrosis, pneumonia)
## Adult Dosing
**Acetaminophen Overdose:**
* **Oral:** 140 mg/kg loading dose, followed by 70 mg/kg every 4 hours for 17 doses.
* **Intravenous:**
* Loading dose: 150 mg/kg over 60 minutes.
* Second infusion: 50 mg/kg over 10 hours.
* Third infusion: 100 mg/kg over 16 hours.
* *Note: IV dosing protocols can vary; consult local guidelines.*
**Thickened Bronchial Secretions:**
* **Inhalation:** 3-5 mL of a 10% or 20% solution, or 1-2 capsules (200 mg each) via nebulizer every 2-6 hours as needed. Dosing frequency and concentration may be adjusted based on patient response and mucus tenacity.
## Pediatric Dosing
**Acetaminophen Overdose:**
* **Oral:** 140 mg/kg loading dose, followed by 70 mg/kg every 4 hours for 17 doses.
* **Intravenous:** Dosing is the same as adults.
**Thickened Bronchial Secretions:**
* **Inhalation:** Similar to adults, 10% or 20% solution (3-5 mL) via nebulizer every 2-6 hours as needed. Concentration and frequency may be adjusted.
## Dose Adjustments
No specific dose adjustments are typically required for renal or hepatic impairment, but caution and close monitoring are advised.
## Contraindications
* Hypersensitivity to acetylcysteine or other components of the formulation.
## Adverse Effects
* **Inhalation:** Bronchospasm, rhinorrhea, nausea, vomiting, stomatitis.
* **Intravenous:** Anaphylactoid reactions (rash, urticaria, angioedema, bronchospasm, hypotension), fever, nausea, vomiting.
* **Oral:** Nausea, vomiting, diarrhea.
## Key Drug Interactions
* **Activated Charcoal:** Can adsorb oral acetylcysteine, reducing its efficacy in acetaminophen overdose. If activated charcoal is used, a higher dose or more frequent administration of acetylcysteine may be necessary.
## Monitoring
* **Acetaminophen Overdose:** Liver function tests (AST, ALT, bilirubin, INR), serum creatinine, glucose, and acetaminophen levels. Monitor for signs of liver injury.
* **Inhalation:** Pulmonary function, presence and tenacity of secretions, signs of bronchospasm.
## Clinical Pearls
* The odor of acetylcysteine is characteristically sulfurous.
* For intravenous administration in acetaminophen overdose, monitor closely for anaphylactoid reactions, especially during the initial loading dose.
* Bronchospasm with inhaled acetylcysteine can be managed with concurrent administration of a bronchodilator.
* Ensure adequate hydration when used for mucolytic purposes.
---
**Disclaimer:** This information is intended for clinical pharmacists and healthcare professionals. It is crucial to consult the most current prescribing information and institutional protocols before administering any medication. Dosing and indications can vary based on patient-specific factors and evolving medical guidelines.
