Mucoactive agents are a class of pharmacologic agents that include expectorants, mucolytics, mucoregulators, and mucokinetics that can affect the volume, viscosity, transportation, and composition of

mucus Mucus (, ) is a slippery aqueous secretion produced by, and covering, mucous membranes. It is typically produced from cells found in mucous glands, although it may also originate from mixed glands, which contain both Serous fluid, serous and muc ...

sputum Sputum is mucus that is coughed up from the lower airways (the trachea and bronchi). In medicine, sputum samples are usually used for a naked-eye examination, microbiological investigation of respiratory infections, and Cytopathology, cytological ...

. They often aid in clearing mucus or sputum from the upper and lower airways. These medications are used to treat respiratory diseases complicated by the oversecretion or inspissation of mucus. These drugs can be further categorized by their

mechanism of action In pharmacology, the term mechanism of action (MOA) refers to the specific biochemical Drug interaction, interaction through which a Medication, drug substance produces its pharmacological effect. A mechanism of action usually includes mention o ...

Mechanism of action

Mucoactive agents—expectorants—include mucolytics, secretolytics and mucokinetics (also called secretomotorics) * Mucolytics: thin (reduce the viscosity of) mucus * Secretolytics: increase airway water or the volume of airway secretions * Mucokinetics: increase mucociliary transport (clearance) and transportability of mucus by cough * Mucoregulators: suppress underlying mechanisms of mucus hypersecretion Alternatively, attacking the affinity between secretions and the biological surfaces is another avenue, which is used by abhesives and

surfactants Surfactants are chemical compounds that decrease the surface tension or interfacial tension between two liquids, a liquid and a gas, or a liquid and a solid. The word ''surfactant'' is a blend of "surface-active agent", coined in 1950. As t ...

. Any of these effects could improve airway clearance during coughing. In general, clearance ability is hampered by the bonding to surfaces (stickiness) and by the

viscosity Viscosity is a measure of a fluid's rate-dependent drag (physics), resistance to a change in shape or to movement of its neighboring portions relative to one another. For liquids, it corresponds to the informal concept of ''thickness''; for e ...

of mucous secretions in the lungs. In turn, the viscosity is dependent upon the concentration of mucoprotein in the secretions. Mucolytics, secretolytics and secretomotorics are different types of medication, yet they are intended to promote drainage of mucus from the lungs. An expectorant (from the Latin ''expectorare'', to expel or banish) works by signaling the body to increase the amount or hydration of secretions, resulting in more, yet clearer, secretions and lubricating the irritated respiratory tract. One mucoactive agent, guaifenesin, has

anxiolytic An anxiolytic (; also antipanic or anti-anxiety agent) is a medication or other intervention that reduces anxiety. This effect is in contrast to anxiogenic agents which increase anxiety. Anxiolytic medications are used for the treatment of anxie ...

and muscle-relaxing properties. It is commonly available in cough syrups and also as sustained-release tablets. Mucolytics can dissolve thick mucus and are usually used to help relieve respiratory difficulties. They do this by breaking down the chemical bonds between molecules in the mucus. This in turn can lower the viscosity by altering the

mucin Mucins () are a family of high molecular weight, heavily glycosylated proteins ( glycoconjugates) produced by epithelial tissues in most animals. Mucins' key characteristic is their ability to form gels; therefore they are a key component in ...

-containing components.

Mucoactive drugs

* Thiols **

acetylcysteine ''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 ...

mesna Mesna, sold under the brand name Mesnex among others, is a medication used in those taking cyclophosphamide or ifosfamide to decrease the risk of hemorrhagic cystitis, bleeding from the bladder. It is used either Oral administration, by mouth or ...

* Thioesters **

carbocisteine Carbocisteine, also called carbocysteine, is a mucolytic that reduces the viscosity of sputum and so can be used to help relieve the symptoms of chronic obstructive pulmonary disorder (COPD) and bronchiectasis by allowing the sufferer to bring u ...

** erdosteine ** mecysteine * Bromhexine-like ** ambroxol ** bromhexine *

DNAse Deoxyribonuclease (DNase, for short) refers to a group of glycoprotein endonucleases which are enzymes that catalyze the hydrolytic cleavage of phosphodiester linkages in the DNA backbone, thus degrading DNA. The role of the DNase enzyme in cells ...

** dornase alpha * Irritative secretolytics **

ammonium chloride Ammonium chloride is an inorganic chemical compound with the chemical formula , also written as . It is an ammonium salt of hydrogen chloride. It consists of ammonium cations and chloride anions . It is a white crystalline salt (chemistry), sal ...

(not believed to work by the FDA)United States Food and Drug Administration
Code of Federal Regulations, Title 21, Volume 5, April 1, 2009
/ref> * Citrates **

potassium citrate Potassium citrate (also known as tripotassium citrate) is a potassium salt of citric acid with the molecular formula K3C6H5O7. It is a white, hygroscopic crystalline powder. It is odorless with a saline taste. It contains 38.28% potassium by mass ...

sodium citrate Sodium citrate may refer to any of the sodium salts of citric acid (though most commonly the third): * Monosodium citrate * Disodium citrate * Trisodium citrate The three forms of salt are collectively known by the E number E331. Applications ...

(not believed to work by the FDA) * Iodides **

Potassium iodide Potassium iodide is a chemical compound, medication, and dietary supplement. It is a medication used for treating hyperthyroidism, in radiation emergencies, and for protecting the thyroid gland when certain types of radiopharmaceuticals are u ...

* Plant-derived compounds or extracts ** guaifenesin (does not work in upper respiratory track infections) **

terpin hydrate Terpin is an expectorant, used to loosen mucus in patients with bronchitis and related conditions. It is used as the hydrate (terpin·H2O). It is derived from sources such as turpentine, oregano, thyme, and eucalyptus. It was used in the United ...

(not believed to work by the FDA) **

tolu balsam Tolu balsam or balsam of Tolu is a balsam that originates from South America (Colombia, Peru, Venezuela). It is similar to (and frequently confounded with) the balsam of Peru. It is tapped from the living trunks of '' Myroxylon balsamum var. b ...

(not believed to work by the FDA) ** '' Justicia adhatoda'' extracts

References

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External links

National Center for Biotechnology Information
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