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1. promoting expectoration.
2. an agent that so acts.
liquefying expectorant an expectorant that promotes the ejection of mucus from the respiratory tract by decreasing its viscosity.

guaifenesin (glyceryl guaiacolate)

Balminil Expectorant (CA), Benilyn Childrens Chesty Coughs (UK), Benylin-E (CA), Calmylin Expectorant (CA), Diabetic Tussin EX, Genatuss, Koffex Expectorant (CA), Mucinex, Organidin NR, Phanacin XPECT, Pneumomist, Resyl (CA), Robitussin, Robitussin Chesty Cough (UK), Scot-tussin Expectorant, Siltussin SA, Tixylix Chesty Cough (UK), Venos for Kids (UK), Vicks Vaposyrup for Chesty Coughs (UK)

Pharmacologic class: Propanediol derivative

Therapeutic class: Expectorant

Pregnancy risk category C


Exerts vasoconstrictive action that leads to decreased edema and congestion. Also increases respiratory secretions and reduces mucus viscosity.


Capsules: 200 mg

Oral solution: 100 mg/5 ml, 200 mg/5 ml

Syrup: 100 mg/5 ml

Tablets: 100 mg, 200 mg, 400 mg

Tablets (extended-release): 600 mg

Indications and dosages

Cough due to upper respiratory tract infection

Adults: 200 to 400 mg P.O. q 4 hours (not to exceed 2,400 mg/day), or 600 to 1,200 mg P.O. (extended-release tablets) q 12 hours (not to exceed 2,400 mg/day)

Children ages 6 to 12: 100 to 200 mg P.O. q 4 hours (not to exceed 1,200 mg/day), or 600 mg P.O. (extended-release) q 12 hours (not to exceed 1,200 mg/day)

Children ages 2 to 6: 50 to 100 mg P.O. q 4 hours (not to exceed 600 mg/day)


• Hypersensitivity to drug

• Alcohol intolerance (with some products)


Use cautiously in:

• diabetes mellitus, cough lasting more than 1 week or accompanied by fever, rash, or headache

• patients receiving disulfiram concurrently

• pregnant patients.


• Give with full glass of water.

Adverse reactions

CNS: headache, dizziness

GI: nausea, vomiting, diarrhea, stomach pain

Skin: rash, urticaria


Drug-diagnostic tests. Urinary 5-hydroxyindoleacetic acid, vanillylmandelic acid: inaccurate results

Patient monitoring

• Assess cough quality and productivity. Reevaluate treatment if cough persists and is accompanied by fever or headache.

Patient teaching

• Tell patient to take with 8 oz of water and to drink plenty of fluids.

• Instruct patient to contact prescriber if cough lasts more than 1 week.

• Caution patient to avoid driving and other hazardous activities until he knows how drug affects concentration and alertness.

• As appropriate, review all other significant adverse reactions and interactions, especially those related to the tests mentioned above.


An expectorant that allegedly reduces the viscosity of sputum, thus facilitating its elimination.


/guai·fen·e·sin/ (gwi-fen´ĕ-sin) an expectorant believed to act by reducing sputum viscosity.


An expectorant drug, C10H14O4, that is used to thin mucus and sputum.


glyceryl guaiacolate, a white to slightly gray powder with a bitter taste and faint odor, widely used as an expectorant. Guaifenesin increases the flow of fluid in the respiratory tract, reducing the viscosity of bronchial and tracheal secretions and facilitating their removal by the cough reflex and ciliary action. It may increase the risk of hemorrhage in patients taking heparin.


Monafed® Common cold An OTC agent for relief of cold/cough. See Common cold.


An expectorant that allegedly reduces the viscosity of sputum, thus facilitating its elimination.


An expectorant that allegedly reduces viscosity of sputum, thus facilitating its elimination.


the glyceryl ester of guaiacol; used as an expectorant and as a muscle relaxant in anesthetic procedures.
References in periodicals archive ?
29) Medications that present the most difficulty are those that patients often become physically or psychologically dependent on, such as benzodiazepines, guaifenesin, proton-pump inhibitors, nonsteroidal anti-inflammatory drugs, and SSRIs.
In our study, 74% of patients with a diagnosis of asthma received guaifenesin.
Adams markets six patent-protected extended-release guaifenesin products over-the-counter under the Mucinex brand name, including a new line of 1200 mg maximum-strength products.
The PA examined the patient, arrived at a provisional diagnosis of viral syndrome and selected ventolin inhaler, cough syrup, Motrin, and Guaifenesin for her treatment.
At a separate inquiry, Martin Wilesmith was fined pounds 600 and All Weather was disqualified from second in the Peter Hamer Memorial Hunters' Chase at Newbury on March 5 after the gelding's urine sample showed evidence of guaifenesin, a muscle relaxant and cough mixture ingredient.
Guaifenesin and methocarbamol can be differentiated with p-dimethylaminobenzaldehyde, because methocarbamol is a carbamate and guaifenesin is not.
Mucous thinning agents such as guaifenesin or organic iodine may be employed.
Tenders are invited for Sugar Free Cough Syrup-Containing Minimum Guaifenesin Or Guaiphenesin 100 Mg Plus Chlorpheniramine Maleate 4 Mg Plus Phenylephrin 5 Mg Plus Dextromethorphan 10 Mg In A Non- Syrup Flavoured Base - 100 Ml.