"It doesn't really help clear out mucus," the study's lead author, Dr. Bruce Rubin, chair of the Department of Pediatrics at the Virginia Commonwealth University Medical Center, told CBSNews.com.
GGE is a FDA-approved expectorant and has been used in brands like Mucinex.
For the study, a total of 295 adults with a cold or cough went through an eight-day, multi-center clinical trial where they were given two 600-mg extended-release GGE tablets (Mucinex) or a placebo twice a day.
At the conclusion of the study, researchers concluded that "extended-release GGE administered at the recommended dose is no more effective than a placebo in changing sputum properties."
Although the study focused on whether or not it was effective in getting rid of the mucus buildup, researchers say that doesn't mean taking cold medicine will have no impact.
"It doesn't mean it won't make you feel better," Rubin said.
The study was paid for and requested by Mucinex. CBS News' requests for comment on the study from Mucinex were not immediately returned.
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