Acetylcysteine

Acetylcysteine
Clinical data
Pronunciation	/əˌsiːtəlˈsɪstiːn/ and similar (/əˌsɛtəl-, ˌæsɪtəl-, -tiːn/)
Trade names	ACC 200, Acetadote, Fluimucil, Mucomyst, others
Other names	N-acetylcysteine; N-acetyl-L-cysteine; NALC; NAC
AHFS/Drugs.com	Monograph
License data	US DailyMed: Acetylcysteine;
Pregnancy; category	AU: B2;
Routes of; administration	oral, intravenous, inhalation
ATC code	R05CB01 (WHO) S01XA08 (WHO) V03AB23 (WHO);
Legal status
Legal status	AU: S4 (Prescription only) or S2; NZ: Prescription only; UK: POM (Prescription only); US: ℞-only;
Pharmacokinetic data
Bioavailability	6–10% (Oral); nearly 100% (intravenous)
Protein binding	50 to 83%
Metabolism	Liver
Elimination half-life	5.6 hours
Excretion	Kidney (30%), faecal (3%)
Identifiers
	IUPAC name (2R)-2-acetamido-3-sulfanylpropanoic acid;
CAS Number	616-91-1 ;
PubChem CID	12035;
DrugBank	DB06151 ;
ChemSpider	11540 ;
UNII	WYQ7N0BPYC;
KEGG	D00221 ;
ChEBI	CHEBI:28939 ;
ChEMBL	ChEMBL600 ;
CompTox Dashboard (EPA)	DTXSID5020021 ;
ECHA InfoCard	100.009.545
Chemical and physical data
Formula	C5H9NO3S
Molar mass	163.19 g·mol−1
3D model (JSmol)	Interactive image;
Specific rotation	+5° (c = 3% in water)
Melting point	109 to 110 °C (228 to 230 °F)
	SMILES C/C(=N/[C@@H](CS)C(=O)O)/O;
	InChI InChI=1S/C5H9NO3S/c1-3(7)6-4(2-10)5(8)9/h4,10H,2H2,1H3,(H,6,7)(H,8,9)/t4-/m0/s1 ; Key:PWKSKIMOESPYIA-BYPYZUCNSA-N ;
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N-acetylcysteine, also known as Acetylcysteine and NAC, is a mucolytics that is used to treat paracetamol (acetaminophen) overdose and to loosen thick mucus in individuals with chronic bronchopulmonary disorders, such as pneumonia and bronchitis. It has been used to treat lactobezoar in infants. It can be taken intravenously, orally (swallowed by mouth), or inhaled as a mist by use of a nebulizer. It is also sometimes used as a dietary supplement.

Common side effects include nausea and vomiting when taken orally. The skin may occasionally become red and itchy with any route of administration. A non-immune type of anaphylaxis may also occur. It appears to be safe in pregnancy. For paracetamol overdose, it works by increasing the level of glutathione, an antioxidant that can neutralize the toxic breakdown products of paracetamol. When inhaled, it acts as a mucolytic by decreasing the thickness of mucus.

Acetylcysteine was initially patented in 1960 and came into medical use in 1968. It is on the World Health Organization's List of Essential Medicines. It is available as a generic medication.

The sulfur-containing amino acids cysteine and methionine are more easily oxidized than the other amino acids.