Antihistamine. Metabolite of hydroxyzine. Molecular weight: 461.82.
"In mice, rats, and rabbits, cetirizine was not teratogenic at oral doses up
to 96, 225, and 135 mg/kg, respectively (approximately 40, 180 and 220 times the
maximum recommended daily oral dose in adults on a mg/m 2 basis)".
In a prospective, controlled, observational study of women exposed to either hydroxyzine or cetirizine during pregnancy
39 women were exposed to cetirizine during organogenesis. Most of the women
had been treated with cetirizine for rhinitis or urticaria. There were no significant differences
found between the cetirizine group and a control group in the rates of
major or minor anomalies, spontaneous abortions, stillbirths, mean birth
weight, mode of delivery, gestational age, or presence of neonatal distress
In an observational study of newly
marketed drugs prescribed in England cetirizine was taken during the
first trimester in 20 pregnancies. One patient chose to have an elective
abortion. There were 4 spontaneous abortions. The remaining mothers
delivered 16 normal infants (one set of twins) .
The American College of Obstetricians and Gynecologists (ACOG) and The
American College of Allergy, Asthma and Immunology (ACAAI) recommend chlorpheniramine and tripelennamine as the
antihistamines of choice for pregnant women. Cetirizine and loratadine
may be considered (preferably after the first trimester) in patients who
cannot tolerate or do not respond to maximal doses of topical therapy. 
BREAST FEEDING: Excreted into human milk. Not considered compatible with
breast feeding by the manufacturer .
1. Physicians Desk Reference 57th ed. Montvale, NJ: Thomson PDR;
2.Einarson A, Bailey B, Jung G, Spizzirri D, Baillie M, Koren G.
Prospective controlled study of hydroxyzine and cetirizine in pregnancy. Ann
Allergy Asthma Immunol. 1997 Feb;78(2):183-6.
3. Wilton LV, Pearce GL, Martin RM, et al.: The
outcomes of pregnancy in women exposed to newly marketed drugs in general
practice in England. Br J Obstet Gynaecol 105:882- 889, 1998.
4. The use of newer asthma and
allergy medications during pregnancy. Position Statement. The American
College of Obstetricians and Gynecologists (ACOG) and The American College
of Allergy, Asthma and Immunology (ACAAI). Ann Allergy Asthma Immunol.