Animal studies have not been performed with the combination product. There are no controlled data in human pregnancy.

Dextromethorphan: Available data does not indicate a major teratogenic risk, and a survey study did not show a relationship with congenital malformations.

Guaifenesin: Animal studies are not available. A monitoring study including 197 mother-child pairs that had first trimester guaifenesin exposure showed an increase in inguinal hernias; 1336 any time pregnancy exposures showed no association with malformations.

Pseudoephedrine: A monitoring study of 50,282 mother/child pairs (3082 first trimester sympathomimetic drug exposures, 9719 any time pregnancy exposures) suggested a link to categories of minor malformations (non-life-threatening, no major cosmetic defects) including inguinal hernia and clubfoot. Pseudoephedrine may be associated with gastroschisis, but this may also be caused by maternal health factors. First trimester oral decongestant exposure or maternal smoking may increase the risk of gastroschisis, small intestinal atresia (SIA), and hemifacial microsomia.


US FDA pregnancy category Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

Safety has not been established during pregnancy; use should be avoided during the third trimester of pregnancy.

US FDA pregnancy category: Not assigned

Comments:
-There is no data on use in pregnant women to know this drugs risks, including the risk of fetal harm or reproductive effects.
-Available human data does not demonstrate major teratogenicity with dextromethorphan.
-Fetuses of mothers with slow dextromethorphan may be exposed to higher concentrations, but the clinical significance is unknown.
-According to some authorities dextromethorphan is compatible with pregnancy; low birth defect incidences were seen in surveillance studies.
-Available data do not indicate developmental toxicity with guaifenesin.
-Pseudoephedrine use during the first trimester may be associated with gastroschisis and small intestinal atresia (SIA); data is limited and unconfirmed, risk appears to be low (only identifiable by case-control studies), and may only occur in combination products, but avoidance during the first trimester is nonetheless recommended.

See references

The manufacturer makes no recommendation regarding use during lactation.

Excreted into human milk: Yes (pseudoephedrine); Data not available (dextromethorphan, guaifenesin)
Excreted into animal milk: Data not available (dextromethorphan, guaifenesin)

Comments:
-There is no information regarding this drug on the presence in human milk, the effects on a breastfed infant, or effects on milk production.
-Given dextromethorphan's low molecular weight, excretion into breastmilk is probable.
-Guaifenesin from breast milk is not expected to adversely affect nursing infants at normal parental doses.
-The small amounts of pseudoephedrine (about 4.3 to 5.5% of maternal dose) may cause occasional irritability.
-A single pseudoephedrine dose acutely decreases milk production (average 24%); repeated use interferes with lactation.
-Do not use pseudoephedrine in patients with insufficient milk production or in those just establishing lactation.
-Products with high alcohol content should be avoided during while breastfeeding.

See references