Please check your internet connection and try again.
# Acetylcysteine
## Overview
Acetylcysteine is a mucolytic agent and an antidote for acetaminophen overdose. It works by breaking disulfide bonds in mucoproteins, reducing mucus viscosity, and by replenishing glutathione stores in the liver.
## Primary Indications
* Acetaminophen overdose
* Mucolytic agent (e.g., for cystic fibrosis, chronic obstructive pulmonary disease)
## Adult Dosing
* **Acetaminophen Overdose:**
* **Oral:** Loading dose of 140 mg/kg, followed by 70 mg/kg every 4 hours for 17 doses (total 72 hours). Maximum dose is 140 mg/kg per dose.
* **Intravenous (IV):** Typically a 3-bag (or 4-bag) protocol.
* **Bag 1:** 150 mg/kg in 200 mL of D5W or NS infused over 60 minutes.
* **Bag 2:** 50 mg/kg in 500 mL of D5W or NS infused over 4 hours.
* **Bag 3:** 100 mg/kg in 500 mL of D5W or NS infused over the next 16 hours.
* *Note: IV dosing protocols can vary; consult local institutional guidelines or product labeling for specific details, including continuous infusion rates and durations.*
* **Mucolytic:**
* **Nebulized:** 3 mL of 20% solution (600 mg) or 6 mL of 10% solution (600 mg) every 4-12 hours.
* **Oral:** 200 mg twice daily to 600 mg three times daily.
## Pediatric Dosing
* **Acetaminophen Overdose:** Dosing is the same as adult dosing (140 mg/kg loading, 70 mg/kg every 4 hours for 17 doses orally; IV protocols are also generally the same, but fluid volumes may need adjustment based on patient size).
* **Mucolytic:**
* **Nebulized:** 10% solution: 1-2 mL (100-200 mg) every 2-6 hours. 20% solution: 1 mL (200 mg) every 2-6 hours. The pediatric dose is often weight-based, typically 200 mg per dose, but specific protocols should be consulted.
## Dose Adjustments
* **Renal Impairment:** No specific dose adjustment is generally recommended, but caution should be exercised.
* **Hepatic Impairment:** No specific dose adjustment is generally recommended, but caution should be exercised.
## Contraindications
* Hypersensitivity to acetylcysteine.
## Adverse Effects
* **Common:** Nausea, vomiting, stomatitis (oral); bronchospasm, rhinorrhea, nausea (nebulized); rash, pruritus, urticaria (IV).
* **Rare but Serious:** Anaphylaxis (especially with IV administration), bronchoconstriction.
## Key Drug Interactions
* **Activated Charcoal:** May bind to acetylcysteine and reduce its absorption when given orally for acetaminophen overdose. Separate administration by at least 2 hours.
* **Nitroglycerin:** May potentiate hypotensive effects.
## Monitoring
* **Acetaminophen Overdose:**
* Acetaminophen levels (serial measurements).
* Liver function tests (LFTs).
* Prothrombin time (PT)/International Normalized Ratio (INR).
* Renal function.
* Electrolytes.
* Clinical status (mental status, vital signs).
* **Mucolytic:**
* Pulmonary function.
* Sputum volume and viscosity.
* Bronchospasm.
## Clinical Pearls
* For acetaminophen overdose, prompt administration of acetylcysteine is crucial, ideally within 8-10 hours of ingestion.
* IV acetylcysteine can cause anaphylactoid reactions (flushing, pruritus, rash, hypotension, bronchospasm). Pretreatment with an antihistamine may be considered, and the infusion rate should be carefully monitored.
* Nebulized acetylcysteine has an unpleasant odor and can sometimes worsen bronchospasm; bronchodilators should be readily available.
* Oral acetylcysteine is often better tolerated when mixed with a flavored beverage due to its sulfurous odor and taste.
***
*Disclaimer: This information is intended for healthcare professionals. Always consult the most current prescribing information, product labeling, and institutional protocols before administering any medication. Dosing and guidelines may vary.*
