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Related to N-acetyl cysteine: Acetylcysteine, N-acetylcysteine


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.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

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.

McGraw-Hill Nurse's Drug Handbook, 7th Ed. Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved


, 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.
Farlex Partner Medical Dictionary © Farlex 2012


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.
Segen's Medical Dictionary. © 2012 Farlex, Inc. All rights reserved.


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.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.


, N-acetylcysteine (as'ĕ-til-sis'tē-in)
A mucolytic agent used to prevent liver injury due to acetaminophen toxicity.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012


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.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005


, N-acetylcysteine (as'ĕ-til-sis'tē-in)
A mucolytic agent that reduces the viscosity of mucous secretions.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
N-Acetyl Cysteine Has Both Gastro-Protective and Anti-Inflammatory Effects in Experimental Rat Models: Its Gastro-Protective Effect Is Related to Its In Vivo and In Vitro Antioxidant Properties.
Mehrpour, "The effect of N-acetyl cysteine (NAC) on aluminum phosphide poisoning inducing cardiovascular toxicity: a case-control study," SpringerPlus, vol.
To study the protective effect of antioxidants 3 days after seeding the salts of heavy metals (lead diacetate, cadmium chloride, cobalt chloride and ammonium molybdate), protectors (carnosine, mexidol, EDTA and N-acetyl cysteine) were added in different concentrations (8 wells per group).
NUTRIENTS TO COMBAT ALZHEIMER'S DISEASE Nutrients with Strong Evidence from Human Studies Acetyl-L-carnitine Lipoic acid Panax ginseng N-acetyl cysteine (NAC) Huperzine A Omega-3 fatty acids Vitamin D Ginkgo biloba Nutrients with Strong Evidence from Epidemiological Studies Coffee Vitamin E Magnesium Nutrients with Strong Laboratory and Theoretical Evidence B vitamins Blueberry extracts CoQ10 PQQ Curcumin Grape seed extract Green tea Resveratrol Vinpocetine Ashwagandha LE: Are there any dietary or lifestyle strategies to reduce the risk of Alzheimer's?
Using an adjunctive strong antioxidant, such as N-acetyl cysteine, (8) with an antipsychotic might help neutralize destructive effects of free radicals and protect the brain from tissue loss during a psychotic episode.
To test for specificity of LBE-induced ROS formation, the HT-29 cells were co-treated with LBE and one of the following anti-oxidants, N-acetyl cysteine, glutathione, a-Tocopherol or ascorbic acid, with results demonstrating significant reduction in ROS formation.
v tid, oral vitamin c (500 mg) qid, vitamin E (400 mg), N-acetyl cysteine, antiemetics, antacid syrup, and local applications of lignocaine, metrogyl, povidine iodine mouth wash.
N-acetyl cysteine, a water-soluble precursor of glutathione, enhancing glutathione synthesis, is one of the antioxidant supplements used in exercise training (32).
The following compounds were purchased from Sigma Aldrich (Taufkirchen, Germany): paclitaxel (PTX), 5-Fluorouracil (5-FU), menadione (MD), tert-butyl hydroperoxide (TBHP), N-acetyl cysteine (NAC), glutathione (GSH), 3H-1, 2-dithiole-3-thione (D3T), [alpha]-Tocopherol ([alpha]-TOC), ascorbic acid (AA).
Evidence for the counterintuitive idea that oxygen radicals are beneficial came from experiments in which researchers gave animals an antioxidant called N-acetyl cysteine. The compound blocked caloric restriction's healthful effects.
The patient was hospitalised in the intensive care unit (ICU) and symptomatic therapy fluid resuscitation N-acetyl cysteine infusion fresh frozen plasma were commenced.
(12) evaluated the effect of treatment with N-acetyl cysteine as a NO donor plus folic acid in patients with unexplained recurrent pregnancy loss and found a significant increase in the take-home baby rate as compared to treatment with folic acid alone.

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