Guaifenesin (gwi fen' ə sin) (INN) or guaiphenesin (former BAN) is an expectorant drug usually taken orally to assist the expectoration ("bringing up") of phlegm from the airways in acute respiratory tract infections. Guaifenesin works by drawing water into the bronchi. The water both thins mucous and lubricates the airway, facilitating the removal of mucous by coughing. It is sold under several brand names such as Humibid, Mucinex, Benylin and Robitussin, and it also is included in many over-the-counter cough and cold remedies. more...
Guaifenesin's molecular formula is C10H14O4, and its chemical name is 3-(2-methoxyphenoxy)-1,2-propanediol. Its CAS number is 93-14-1. It was first approved by the FDA in 1952.
Guaifenesin is also used in the experimental guaifenesin protocol in the treatment of fibromyalgia.
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