Please check your internet connection and try again.
# Acetylcysteine
## Overview
Acetylcysteine is a mucolytic agent that loosens thick mucus, making it easier to clear from the airways. It also acts as an antidote for acetaminophen overdose by replenishing glutathione stores.
## Primary Indications
* **Acetaminophen overdose:** As an antidote.
* **Thick mucus secretions:** In conditions such as cystic fibrosis, chronic bronchitis, emphysema, and pneumonia.
## Adult Dosing
* **Acetaminophen overdose:**
* **Loading dose:** 150 mg/kg IV over 1 hour.
* **Second infusion:** 50 mg/kg IV over 16 hours.
* **Alternative (oral):** 140 mg/kg PO, followed by 70 mg/kg PO every 4 hours for 17 doses.
* *Note:* IV dosing is preferred in severe overdose or if vomiting is prominent. The total daily dose of IV acetylcysteine should not exceed 300 mg/kg. Higher doses may be used in severe cases based on specific protocols.
* **Mucolytic:**
* **Inhaled:** 1-10 mL of a 10% or 20% solution every 2-6 hours as needed, or 3-5 mL of a 20% solution TID-QID.
* **Oral:** 200 mg (e.g., 1 capsule or 200 mg effervescent tablet) 2-3 times daily. For granules, 600 mg once daily.
* **Nebulized (in specific settings):** Dosing may vary, often 5-10 mL of a 10% or 20% solution.
## Pediatric Dosing
* **Acetaminophen overdose:**
* **Loading dose:** 150 mg/kg IV over 1 hour.
* **Second infusion:** 50 mg/kg IV over 16 hours.
* **Alternative (oral):** 140 mg/kg PO, followed by 70 mg/kg PO every 4 hours for 17 doses.
* *Note:* IV dosing is generally preferred for children, especially neonates and infants, due to absorption variability and risk of vomiting with oral administration. Dosing is typically weight-based as above, regardless of age, though specific protocols may exist for neonates.
* **Mucolytic:**
* **Inhaled:**
* Infants and children < 6 years: 1-2 mL of a 10% or 20% solution every 2-6 hours.
* Children > 6 years: 3-5 mL of a 20% solution or 6-10 mL of a 10% solution every 2-6 hours.
* **Oral:** Dosing is less well-established in pediatrics; often 200 mg BID or TID depending on age and formulation. For granules, 600 mg once daily in children > 12 years.
## Dose Adjustments
* **Renal Impairment:** No specific dose adjustment is typically recommended, but caution may be advised in severe impairment.
* **Hepatic Impairment:** No specific dose adjustment is typically recommended for mucolytic use. For acetaminophen overdose, severe hepatic impairment may necessitate closer monitoring and consideration of alternative agents or protocols.
## Contraindications
* Hypersensitivity to acetylcysteine or any component of the formulation.
* Acute exacerbation of asthma (inhaled use, use with extreme caution).
## Adverse Effects
* **Inhaled:** Bronchospasm, bronchoconstriction, rhinorrhea, nausea, vomiting, stomatitis.
* **IV:** Anaphylactoid reactions (rash, urticaria, pruritus, angioedema, tachycardia, hypotension, bronchospasm), fever, chills.
* **Oral:** Nausea, vomiting, diarrhea, abdominal pain, stomatitis.
## Key Drug Interactions
* **Activated Charcoal:** May adsorb oral acetylcysteine, reducing absorption. Administer acetylcysteine at least 1 hour after charcoal.
* **Nitroglycerin:** May potentiate hypotensive effects. Monitor blood pressure.
## Monitoring
* **Acetaminophen overdose:** Serum acetaminophen levels, liver function tests (ALT, AST, bilirubin, INR), glucose, electrolytes, BUN, creatinine.
* **Mucolytic use:** Respiratory status, signs of bronchospasm, sputum production.
* **IV infusion:** Vital signs (blood pressure, heart rate, respiratory rate), signs of anaphylaxis.
## Clinical Pearls
* For inhaled use, pre-treatment with a bronchodilator may be necessary to prevent bronchospasm.
* The odor of acetylcysteine is unpleasant and can be a barrier to adherence.
* IV acetylcysteine for acetaminophen overdose has a high success rate when initiated promptly. Time to treatment is critical.
* Dilute IV acetylcysteine with compatible IV fluids (e.g., D5W, NS) as per manufacturer guidelines to reduce infusion-related reactions.
* Oral acetylcysteine can be mixed with juice or cold non-carbonated beverages to mask the odor and taste.
**Disclaimer:** This information is intended for healthcare professionals. Always consult the official prescribing information and institutional protocols for complete details before administering any medication. Dosing and indications may vary based on specific clinical situations and patient factors.
