Expectorant

Expectorant refers to a therapeutic class of drugs that aid in the clearance of mucus from the respiratory tract and is not a specific molecular target, receptor, or enzyme (StatPearls). The primary biological function of these agents is to increase the volume and decrease the viscosity of bronchial secretions, thereby facilitating their removal through the cough reflex and mucociliary transport (NIH). For example, guaifenesin, the most common expectorant, is thought to work by irritating gastric vagal receptors to trigger a gastro-pulmonary reflex that stimulates the secretion of thinner fluid in the airways (PubMed, PubChem). These agents are widely used to treat productive coughs associated with the common cold, acute bronchitis, and chronic obstructive pulmonary disease (COPD) (NIH). Because 'Expectorant' describes a broad pharmacological action rather than a distinct biological molecule, it is categorized as an incorrect entry for a specific therapeutic target in molecular databases (UniProt).

Other names

MucolyticSecretolyticMucoactive agent

Expectorants facilitate the removal of mucus by increasing the volume and reducing the viscosity of respiratory tract secretions. This is primarily achieved through the stimulation of gastric vagal receptors, which triggers a gastro-pulmonary reflex that increases airway fluid secretion, or by direct action on the bronchial glands to alter mucin production and hydration (PubMed, StatPearls).