Guaifenesin

Guaifenesin, also known as glyceryl guaiacolate, which is sold under many brand names including Mucinex, is an expectorant medication taken by mouth and marketed as an aid to eliminate sputum from the respiratory tract. Chemically, it is an ether of guaiacol and glycerine. It may be used in combination with other medications. A 2014 study found that guaifenesin does not affect sputum volume in upper respiratory infections (the upper respiratory system includes most breathing parts above the lungs). In 2023, guaifenesin was alleged to work by increasing the liquid content in airway secretions. Side effects may include dizziness, sleepiness, skin rash, and nausea. While it has not been properly studied in pregnancy, it appears to be safe. Guaifenesin has been used medically since at least 1933. It is available as a generic medication and over-the-counter (OTC). In 2023, it was the 291st most commonly prescribed medication in the United States, with more than 500,000 prescriptions. In 2023, the combination dextromethorphan/guaifenesin was the 315th most commonly prescribed medication in the United States, with more than 200,000 prescriptions.