Mucoproteins, linkages

Pharmacology The mucolytic action of acetylcysteine is related to the sulfhydryl group in the molecule, which acts directly to split disulfide linkages between mucoprotein molecular complexes, resulting in depolymerization and a decrease in mucus viscosity. The mucolytic activity of acetylcysteine increases with increasing pH. 

Mechanism of Action An intratracheal respiratory inhalant that splits the linkage of mucoproteins, reducingtheviscosityof pulmonary secretions.Tiierapeutic Effect Facilitates the removal of pulmonary secretions by coughing, postural drainage, mechanical means. Protects against acetaminophen overdose-induced hepatotoxicity. Pharmacokinetics Protein binding 83% (injection). Rapidly and extensively metabolized in liver. Deacetylated by the liver to cysteine and subsequently metabolized. Excreted in urine. Half-life 5.6 hr (injection). 

Acetylcysteine decreases thickness of mucous secretions in lung. As a mucolytic agent, acetylcysteine splits disulfide linkages between mucoprotein molecular complexes, decreasing their viscosity. It is used as an adjunct therapy in emphysema with bronchitis, chronic asthmatic bronchitis, mberculosis, bronchiectasis, primary amyloidosis of the lung, pneumonia, and tracheobronchitis. In addition, it is used in pulmonary complications of cystic fibrosis and those associated with anesthetics, surgery, or care following tracheostomy. 

A. Mucoproteins. Dissociable complexes with salt linkages, or possibly mixtures. 

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