Mucoactive agent

Mucoactive agents are a class of chemical agents that aid in the clearance of mucus from the upper and lower airways, including the lungs, bronchi, and trachea. Mucoactive drugs include expectorants, mucolytics, mucoregulators, and mucokinetics. These medications are used in the treatment of respiratory diseases that are complicated by the oversecretion or inspissation of mucus. These drugs can be further categorized by their mechanism of action.
Mechanism of action.
In general, clearance ability is hampered by the bonding to surfaces (stickiness), and by the viscosity of mucous secretions in the lungs. In turn, the viscosity is dependent upon the concentration of mucoprotein in the secretions.
Expectorants and mucolytic agents are different types of medication, yet both 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 as a byproduct lubricating the irritated respiratory tract.
One expectorant, guaifenesin, is commonly available in many cough syrups and also as long 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-containing components.
Alternatively, attacking the affinity between secretions and the biological surfaces is another avenue, which is used by abhesives and surfactants.
Any of these effects could improve airway clearance during coughing.
Mucoactive drugs.
Many mucoactive drugs are available, including sodium citrate or potassium citrate, potassium iodide, guaifenesin, tolu balsam, vasaka, and ammonium chloride.
Mucolytic drugs available include acetylcysteine, ambroxol, bromhexine, carbocisteine, erdosteine, mecysteine, and dornase alfa.