The Asthma Center


Mucolytics/expectorants are medications that promote the discharge or expulsion of mucus from the respiratory tract. They can change the physical properties of the mucus by thinning it. These medications also increase the ability of cilia to clear and drain mucus. Thinner mucus can be more easily penetrated by other medications such as antibiotics.

Guaifenesin is the most commonly prescribed mucolytic. It is often found in many over the counter liquid cough medications. Guaifenesin is also available in tablet form over the counter (Mucinex). In higher doses, it is available by prescription in combination with a decongestant or cough medication. Examples include: Pseudovent PED, Entex LA, Mucinex D and Muco-Fen DM.

Risks and Precautions
Some expectorant preparations contain iodides (potassium iodide) that may result in the development of a goiter (swollen thyroid gland), a severe rash, or salivary gland inflammation. These medications are not recommended for use in children, pregnant women, or individuals with thyroid conditions.

Guaifenesin may cause nausea and vomiting. Taking guaifenesin with food may decrease these side effects.

Codeine is sometimes found in expectorants. This medication actually suppresses the cough reflex. It should be noted that codeine is a narcotic with side effects of constipation as well as the potential