Acetyl%252525252525252525252520cysteine

# Acetylcysteine ## Overview Acetylcysteine is a mucolytic agent that reduces the viscosity of pulmonary secretions by splitting disulfide bonds; it also serves as a glutathione precursor used as an antidote for acetaminophen toxicity. ## Primary Indications * **Acetaminophen Toxicity:** Antidote to prevent hepatotoxicity. * **Mucolytic Therapy:** Adjuvant in abnormal, viscid, or inspissated mucous secretions (e.g., COPD, cystic fibrosis, pneumonia). * **Contrast-Induced Nephropathy (Off-label):** Prevention in high-risk patients. ## Adult Dosing * **Acetaminophen Toxicity (IV - Acetadote):** * Loading: 150 mg/kg IV over 60 minutes. * Second Dose: 50 mg/kg IV over 4 hours. * Third Dose: 100 mg/kg IV over 16 hours. * *Follow regional/hospital-specific protocols (e.g., Rumack-Matthew nomogram).* * **Inhalation (Mucolytic):** 1–10 mL of 20% solution or 2–20 mL of 10% solution via nebulizer q4–6h. ## Pediatric Dosing * **Acetaminophen Toxicity (IV):** Same weight-based regimen as adults (150 mg/kg, 50 mg/kg, 100 mg/kg). * **Inhalation (Mucolytic):** 3–5 mL of 20% solution or 6–10 mL of 10% solution via nebulizer q6–8h. ## Dose Adjustments * **Hepatic/Renal Impairment:** No standard adjustment required for nebulized therapy; IV dosing for toxicity typically remains unchanged, though clinical monitoring for fluid overload is required. ## Contraindications * Hypersensitivity to the drug or vehicle components. * Asthma (use with extreme caution as inhalation can induce bronchospasm). ## Adverse Effects * **IV:** Anaphylactoid reactions (flushing, pruritus, urticaria, angioedema), hypotension, nausea, vomiting. * **Inhalation:** Bronchospasm (severe in asthmatics), stomatitis, rhinorrhea, nausea. ## Key Drug Interactions * **Adsorbents (Activated Charcoal):** May bind inhaled or oral acetylcysteine; separate administration. * **Nitroglycerin:** Acetylcysteine may enhance nitrate-induced vasodilation and hypotension. ## Monitoring * **Acetaminophen Toxicity:** Serum acetaminophen levels, AST/ALT, bilirubin, INR/PT, creatinine, and electrolytes. Monitor closely for anaphylactoid reactions during IV infusion. * **Mucolytic:** Respiratory status, sputum consistency, and presence of bronchospasm. ## Clinical Pearls * **Bronchospasm:** Always keep a bronchodilator (e.g., albuterol) available when administering via nebulization. * **Odor:** The nebulized solution contains sulfur and has a characteristic "rotten egg" odor, which may cause patient nausea. * **IV Anaphylaxis:** In cases of mild anaphylactoid reactions (e.g., flushing) during IV infusion, stopping the infusion, starting an antihistamine, and restarting at a slower rate may be appropriate per institutional protocol. *** **Educational Disclaimer:** This information is for educational purposes only. Always verify dosing, contraindications, and compatibility with local institutional protocols, current package inserts, or clinical decision support tools (e.g., Lexicomp, Micromedex) before prescribing or administering medication.