Pharmacology: Guaifenesin is believed to produce its effect through a local or reflex irritant action that activates the vagus nerve to stimulate secretion or respiratory tract fluid. This is thought to increase sputum volume, decrease its viscosity, enhance the flow of less viscid secretions and promote mucociliary clearance.
Pharmacokinetics: The drug is rapidly absorbed from the gastrointestinal tract and excreted in the urine.
Indications: An expectorant agent used in the symptomatic relief of respiratory conditions associated with productive cough, with the presence of mucus in the respiratory tract. May also be useful in the management of dry, unproductive cough by easing expectoration of thick, viscous secretions.
Precautions: Consult a physician if cough persists for longer than 7 days or if high fever, skin rash, persistent headache, or sore throat is present with cough.
Guaifenesin may cause a color interference with certain laboratory determinations of 5-hydroxyindoleacetic acid and vanillylmandelic acid.
Adverse Effects: Nausea, gastrointestinal upset and drowsiness occur infrequently.
GUAIFENESIN General MonographGlyceryl GuaiacolateExpectorant