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a mucolytic agent used by instillation or nebulization to reduce the viscosity of respiratory tract secretions and orally or intravenously as an antidote to acetaminophen poisoning.

acetylcysteine (N-acetylcysteine)

Acetadote, Mucomyst (CA), Mucosil-10, Mucosil-20, Parovelex (CA) (UK)

Pharmacologic class: N-acetyl derivative of naturally occurring amino acid (L-cysteine)

Therapeutic class: Mucolytic, acetaminophen antidote

Pregnancy risk category B


Decreases viscosity of secretions, promoting secretion removal through coughing, postural drainage, and mechanical means. In acetaminophen overdose, maintains and restores hepatic glutathione, needed to inactivate toxic metabolites.


Injection: 200 mg/ml

Solution: 10%, 20%

Indications and dosages

Mucolytic agent in adjunctive treatment of acute and chronic bronchopulmonary disease (bronchitis, bronchiectasis, chronic asthmatic bronchitis, emphysema, pneumonia, primary amyloidism of lungs, tuberculosis, tracheobronchitis), pulmonary complications of cystic fibrosis, atelectasis, or pulmonary complications related to surgery, posttraumatic chest conditions, tracheostomy care, or use during anesthesia

Adults and children: Nebulization (face mask, mouthpiece, tracheostomy)-6 to 10 ml of 10% solution or 3 to 5 ml of 20% solution three or four times daily. Dosage range is 2 to 20 ml of 10% solution or 1 to 10 ml of 20% solution q 2 to 6 hours.

Nebulization (tent or croupette)-Volume of 10% or 20% solution that will maintain heavy mist for desired period Instillation (direct)-1 to 2 ml of 10% to 20% solution q 1 hour p.r.n.

Instillation via syringe attached to percutaneous intratracheal catheter-2 to 4 ml of 10% solution or 1 to 2 ml of 20% solution q 1 to 4 hours

Diagnostic bronchial studies

Adults and children: Two to three doses of 2 to 4 ml of 10% solution or 1 to 2 ml of 20% solution by nebulization or intratracheal instillation before procedure

Acetaminophen overdose

Adults, elderly patients, children: Give immediately if 24 hours or less have elapsed since acetaminophen ingestion. Use the following protocol: empty stomach by lavage or emesis induction, and then have patient drink copious amounts of water. If activated charcoal has been given, perform lavage before giving acetylcysteine. Draw blood for acetaminophen plasma assay and baseline aspartate aminotransferase (AST), alanine aminotransferase (ALT), prothrombin time, bilirubin, blood glucose, blood urea nitrogen, electrolyte, and creatinine clearance levels. If ingested acetaminophen dose is in toxic range, give acetylcysteine 140 mg/kg P.O. as loading dose from 20% solution. Administer 17 maintenance doses of 70 mg/kg P.O. q 4 hours, starting 4 hours after loading dose. Repeat procedure until acetaminophen blood level is safe. If patient vomits loading dose or any maintenance dose within 1 hour of administration, repeat that dose.

Off-label uses

• Unstable angina


• Hypersensitivity to drug (except with antidotal use)

• Status asthmaticus (except with antidotal use)


Use cautiously in:

• renal or hepatic disease, Addison's disease, alcoholism, brain tumor, bronchial asthma, seizure disorder, hypothyroidism, respiratory insufficiency, psychosis

• elderly patients

• pregnant or breastfeeding patients.


• Separate administration times of this drug and antibiotics.

• Use plastic, glass, or stainless steel container when giving by nebulizer, because solution discolors on contact with rubber and some metals.

• Once solution is exposed to air, use within 96 hours.

• Dilute solution before administering for acetaminophen overdose, to reduce risk of vomiting, drug's unpleasant odor, and irritating or sclerosing properties.

• Chill solution and have patient sip through straw, or, if necessary, give by nasogastric tube when administering for acetaminophen overdose.

Adverse reactions

CNS: dizziness, drowsiness, headache

CV: hypotension, hypertension, tachycardia

EENT: severe rhinorrhea

GI: nausea, vomiting, stomatitis, constipation, anorexia

Hepatic: hepatotoxicity

Respiratory: hemoptysis, tracheal and bronchial irritation, increased secretions, wheezing, chest tightness, bronchospasm

Skin: urticaria, rash, clamminess, angioedema

Other: tooth damage, chills, fever, hypersensitivity including anaphylaxis


Drug-drug. Activated charcoal: increased absorption and decreased efficacy of acetylcysteine

Nitroglycerin: increased nitroglycerin effects, causing hypotension and headache

Drug-diagnostic tests. Liver function tests: abnormal results

Patient monitoring

• Monitor respirations, cough, and character of secretions.

Patient teaching

• Instruct patient to report worsening cough and other respiratory symptoms.

• Advise patient to mix oral form with juice or cola to mask bad taste and odor.

• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs and tests mentioned above.


, N-acetylcysteine (a-sĕ'til-sis'tē-in),
A mucolytic agent that reduces the viscosity of mucous secretions; used to prevent liver injury produced by acetaminophen toxicity.


/ac·e·tyl·cys·te·ine/ (as″ĕ-til-) (as″ĕ-tēl-sis´te-ēn) a derivative of cysteine used as a mucolytic in various bronchopulmonary disorders and as an antidote to acetaminophen poisoning.


a mucolytic and acetaminophen antidote.
indications It is prescribed in the treatment of chronic pulmonary disease, acute bronchopulmonary disease, atelectasis resulting from mucous obstruction, and acetaminophen poisoning.
contraindication Known sensitivity to this drug prohibits its use.
adverse effects Among the most serious adverse reactions are stomatitis, nausea, rhinorrhea, and bronchospasm.


A mucolytic used to reduce the viscosity of lung secretions, and thought to improve O2 delivery and consumption by replenishing glutathione stores; acetylcysteine is also used orally or IV as an antidote, and minimises hepatocellular necrosis in patients with fulminant liver failure due to acetaminophen overdose. Acetylcysteine has also been used for treating dry eye (keratoconjunctivitis sicca) and as an enema for managing bowel obstruction caused by meconium ileus.


Mucomyst Therapeutics A mucolytic used to ↓ the viscosity of lung secretions, and is thought to improve O2 delivery and consumption by replenishing glutathione stores; acetylcysteine is also used per os or IV as an antidote, and minimizes hepatocellular necrosis in Pts with fulminant liver failure; it has also been used for treating dry eye–keratoconjunctivitis sicca, and as an enema for managing bowel obstruction caused by meconium ileus. See Cystic fibrosis.


, N-acetylcysteine (as'ĕ-til-sis'tē-in)
A mucolytic agent used to prevent liver injury due to acetaminophen toxicity.


A mucolytic drug used to reduce the stickiness and viscosity of MUCUS. It is useful for freeing sputum in bronchitis and in liquefying mucus in CYSTIC FIBROSIS. It improves eye comfort in KERATOCONJUNCTIVITIS SICCA. Acetylcysteine increases the production of the antioxidant glutathione and other antioxidant thiols. It can reduce the risk of kidney damage from X-ray contrast media (contrast nephropathy) and reduce the risk of liver damage from acetaminophen (Paracetamol). It can prolong life in people with idiopathic pulmonary fibrosis. A brand name is Parvolex. Formulated with hypromellose it is marketed as Ilube.


, N-acetylcysteine (as'ĕ-til-sis'tē-in)
A mucolytic agent that reduces the viscosity of mucous secretions.
References in periodicals archive ?
The study also reported that acetylcysteine was well tolerated with good compliance (Back et al.
Taylor, "Acetylcysteine In Diabetes (AID): a randomized study of acetylcysteine for the prevention of contrast nephropathy in diabetics," The American Heart Journal, vol.
Acetylcysteine in the prevention of contrast-induced nephropathy after coronary angiography.
Positive assays would require confirmatory quantitative serum determinations to evaluate the need for antidotal therapy with acetylcysteine.
Acetylcysteine for prevention of acute deterioration of renal function following elective coronary angiography and intervention: A randomized controlled trial.
Periprocedural administration of acetylcysteine reduces the risk of contrast nephropathy in high-risk patients (odds ratio=0.
Acetylcysteine is the antidote of choice after ingestion of toxic amounts of acetaminophen.
The FTC's clearance is contingent upon Pfizer's commitment to divest four US sterile injectable assets, including Acetylcysteine, Clindamycin, Voriconazole and Melphalan.
M2 PHARMA-July 10, 2015-Akorn launches Acetylcysteine Injection in US