VPT 311: General and Systemic Veterinary Pharmacology (2+1)

INGESTED EXPECTORANTS

• Systemic expectorants of diverse origins are available.
• These are all administered by mouth.
• Some are nauseants and can induce vomiting, but are administered in subemetic doses.
• Others are absorbed from the gut and are excreted, at least in part, via the bronchial mucosa.
• Reflex or nauseant expectorants include ipecaacuanha, squill, balsam of tolu and cocillana, all of which are of vegetable origin.
• Ipecacuanha contains an emetic alkaloid, emetine and squill contains a glycoside with emetic and cardiotonic properties.
• Bronchial secretions are stimulated as a physiological prelude to vomiting.
• Locally acting, systemically administered expectorants of value in chronic conditions are represented by sodium iodide and potassium iodide.
• The iodide is rapidly excreted through the bronchial mucosa and increases its secretory activity.
• Ammonium chloride is one of the many ammonium salts, which have been used as expectorants despite lack of agreement as to their mode of action.
• Guiacol and Glyceryl guiacolate (guaifenesin), a derivative of guiacol obtained from creosote are common stimulant expectorants in cough medications,