Mucinex DM is a combination ingredient product containing the following active ingredients:

  • Guaifenesin (expectorant)
  • Dextromethorphan (cough suppressant)


Use of Mucinex DM is generally not recommended for use during pregnancy as there have been few studies completed to determine the safety of the ingredients contained in the product.


Below, we discuss both active ingredients in detail in regard to the information available on use during pregnancy.


Mucinex DM Use While Pregnant

Dextromethorphan

Based on the mechanism of action of dextromethorphan, a codeine derivative, there is some concern regarding its use in pregnant women. There have been however, few studies that have investigated the matter.


One study, completed using chicken embryos as the test subjects, showed dextromethorphan could potentially be teratogenic:


"Taken together, these data indicate that NMDA receptor antagonists [which includes dextromethorphan]....are potent teratogens in the chicken embryo model. Because dextromethorphan is a widely used nonprescription antitussive, its strong teratogeneticity using this model is particularly noteworthy."


Most studies that involve humans however, have not found significant effects on a developing baby. One study reported no adverse events in mothers or the fetus when exposed to dextromethorphan during the first trimester. However, the study was small in scale and more are certainly needed to determine the safety of the drug during pregnancy.


Guaifenesin

The use of guaifenesin is not recommended during pregnancy due to the lack of studies with the drug. The American Academy Of Family Physicians does not recommend use of the drug, citing the lack of studies and isolated reports of neural tube defects in infants. 


Generally, an increase intake of fluids to ease expectoration and thin mucus is recommended as the first line treatment option for pregnant women.


Summary

Use of Mucinex DM (guaifenesin/dextromethorphan) is generally not recommended for use during pregnancy due to the lack of studies evaluating the safety of the product. If you are having symptoms of cough and chest congestion, the first line recommendation is an increase in fluids. Other options may include certain types of cough drops and teas. Be sure to speak with your doctor regarding options to treat your symptoms safely while pregnant.,