Safety has not been established during pregnancy.

AU TGA pregnancy category: A
US FDA pregnancy category: Not Assigned

Comments: This drug is not known to cause birth defects, but studies to prove its safety for the developing fetus have not been performed.

See references

Use should be avoided during breastfeeding or if planning to breastfeed.

Excreted into human milk: Yes

Comments: Small occasional doses of this drug would not be expected to cause any adverse effects in breastfed infants; however, larger doses or more prolonged use may cause drowsiness, unusual excitement, or irritability in nursing infants and/or decrease the milk supply, particularly in combination with a sympathomimetic such as pseudoephedrine or before lactation is well established.

-In one telephone follow-up study, irritability and colicky symptoms were reported in 10% and drowsiness was reported in 1.6% of infants exposed to various antihistamines; none of the reactions required medical attention.
-Relatively high doses of antihistamines given by injection can decrease basal serum prolactin in nonlactating women and in early postpartum women; however, it is unknown whether lower oral doses of antihistamines have the same effect on serum prolactin or whether the effects on prolactin have any consequences on breastfeeding success.

See references