(Medical Xpress)—Glyceryl guaiacolate ether (GGE), the active ingredient in many popular over-the-counter cold remedies, is unlikely to make it easier to cough up phlegm when delivered in the recommended dose, according to a Virginia Commonwealth University study.
A total of 295 subjects completed the eight-day, multi-center clinical trial in which sputum samples were collected and measured for their volume and properties. At the end of the study, authors concluded that "extended–release GGE administered at the recommended dose is no more effective than a placebo in changing sputum properties."
The study was published in the May 2014 issue of the journal Respiratory Care. Bruce Rubin, M.D., the Jessie Ball DuPont Distinguished Professor and chair of the Department of Pediatrics at the VCU Medical Center and physician-in-chief of the Children's Hospital of Richmond at VCU, is a lead author.
"This study is consistent with smaller studies that have shown that guaifenesin has no measurable effect on sputum properties or mucus clearance when taken by otherwise healthy adults who get a common cold," Rubin said. "Although we did not study people with chronic bronchitis or other mucus problems, it is very unlikely that any benefit perceived by people who take medications containing guaifenesin is due to clearing out airway mucus."
Agathe Hoffer-Schaefer, Henry J Rozycki, Melissa A Yopp, and Bruce K Rubin, "Guaifenesin Has No Effect on Sputum Volume or Sputum Properties in Adolescents and Adults With Acute Respiratory Tract Infections," Respir Care, May 2014 59:5 631-636; published ahead of print September 3, 2013, DOI: 10.4187/respcare.02640