The study is designed to meet regulatory requirement outside the US. The dosing regimen and assessments timepoints were dictated by immediate release (IR) guaifenesin (GGE) and do not match approved Mucinex labeling in the U.S. The purpose of this study is to determine whether Mucinex is effective and non-inferior as compared to placebo and immediate release guaifenesin in the treatment of symptoms of acute upper respiratory infections. This design was required based on EU regulatory guidance.