Mucolytics

Mucolytics reduce the viscosity of tenacious and purulent mucus, thus faciUtating removal. The distinction between mucolytics and other classes of expectorants is frequently blurred. Steam, sometimes in conjunction with surfactants or volatile oils, has long been used to decrease viscosity by physical hydration. However, agents that chemically depolymerize certain components of mucus are available. Trypsin and other proteolytic enzymes have shown good clinical activity because of their abiUty to cleave glycoproteins. Pancreatic domase, which depolymerizes DNA found in purulent mucus, also has shown clinical utihty. 

Several mucolytics reduce the viscosity of mucus by cleaving the disulfide bonds that maintain the gel stmcture. AJ-Acet l-L-cysteine [616-91 -1] (19), introduced in 1963, and mesna [19677-45-5] (20), developed in Europe in the early 1970s (20,21), are effective compounds in this class. Whereas most mucolytics must be adrninistered by aerosol, carbocysteine [638-23-6] (21), which contains a derivatized sulfhydryl group, has shown activity by the oral route (22,23). However, carbocysteine does not reduce mucus viscosity, as does acetylcysteine, but appears to have a direct action on mucus glycoprotein production (24). 

Therapeutic Function Mucolytic expectorant nasal antiinfective Chemical Name S-(carboxymethyl)-L-cysteine Common Name —... 

Mucolytic and anti-oxidant drugs include ambroxol, N-acetylcysteine, carbocysteine and iodinated glycerol. These drugs have no proven effect on lung function. At... 

Discuss important preadministration and ongoing assessment activities the nurse should perform on patients receiving an antitussive, mucolytic, or expectorant drug. 

LJpper respiratory infections are among die most common afflictions of humans. The drug used to treat die discomfort associated widi an upper respiratory infection include antitussives, mucolytics, and expectorants. Many of tiiese dm are available as nonprescription (over-die-counter) dni, whereas otiiers are available only by prescription. 

Use of codeine may result in respiratory depression, euphoria, light-headedness, sedation, nausea, vomiting, and hypersensitivity reactions. The more common adverse reactions associated with the antitussives are listed in the Summary Drug Table Antitussive, Mucolytic, and Expectorant Drugs. When used as directed, nonprescription cough medicines containing two or more ingredients have few adverse reactions. However, those that contain an antihistamine may cause drowsiness. 

A mucolytic is a drug that loosens respiratory secretions. An expectorant is a drug that aids in raising diick, tenacious mucus from the respiratory passages. 

A drug with mucolytic activity appears to reduce the viscosity (thickness) of respiratory secretions by direct action on the mucus. An example of a mucolytic drug is acetylcysteine (Mucomyst). 

The mucolytic acetylcysteine may be used as part of the treatment of bronchopulmonary diseases such as emphysema It is primarily given by nebulization but also may be directiy instilled into a tracheostomy to liquefy (thin) secretions. The mucolytic drugs are effective as adjunctive therapy in chronic bronchopulmonary diseases, such as chronic emphysema, emphysema with... 

The more common adverse reactions associated with mucolytic and expectorant dm are listed in die Summary Drug Table Antitussive, Mucolytic, and Expectorant Dru i. 

The expectorants and mucolytics are contraindicated in patients with known hypersensitivity. The expectorant potassium iodide is contraindicated during pregnancy (Pregnancy Category D). 

Immediately before and after treatment with the mucolytic acetylcysteine, the nurse auscultates the lung and records the finding of both assessments on the patient s chart. Between treatments, the nurse evaluates the patient s respiratory status and records these finding on the patient s chart. These evaluations aid the primary health care provider in determining the effectiveness of therapy. If any problem occurs during or after treatment, or if the patient is uncooperative, the nurse discusses the problem with the primary health care provider. 

Promoting an Optimal Response to Therapy When the mucolytic acetylcysteine is administered by nebulization, the nurse explains the treatment to the... 

The patient and family demonstrate an understanding of the drug regimen and use of equipment to administer the drug (mucolytic). 

Unit V has three chapters concerning drugs that affect the respiratory system. The first chapter in this unit discusses antihistamines and decongestants, the second chapter in the unit covers bronchodilators and antiasthma drugs, and the last chapter of the unit deals with antitussives, mucolytics, and expectorants. 

Of course, the influence of organic solvents on enzyme enantioselectivity is not limited to proteases but it is a general phenomenon. Quite soon, different research groups described the results obtained with lipases [28]. For instance, the resolution of the mucolytic drug ( )-trans-sobrerol (11) was achieved by transesteriflcation with vinyl acetate catalyzed by the lipase from Pseudomonas cepacia adsorbed on celite in various solvents. As depicted in Scheme 1.3 and Table 1.5, it was found that t-amyl alcohol was the solvent of choice in this medium, the selectivity was so high ( >500) that the reaction stopped spontaneously at 50% conversion giving both +)4rans-sobrerol and (—)-trans-sobrerol monoacetate in 100% optical purity [29]. 

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