Antihistamines – Are these a bad cocktail?

By : Jennifer Agard, M.D.

Seasonal allergies are one of the most common ailments in couples undergoing In Vitro Fertilization (IVF). But many women are unclear whether they can use anti-histamines? To further complicate matters, some fertility forums discuss individual use of anti-histamines to improve pregnancy rates during IVF when patients have a history of recurrent pregnancy loss. Others strictly warn against anti-histamines, quoting a potential risk of vaso-constriction or reducing blood flow to the ovaries and uterus, as it acts in the nasal passages. So what’s a woman to do?

At present, there are no well designed clinical studies that have evaluated the effect of anti-histamine use on fertility. Research has shown that there are histamine receptors in the uterus1, that human embryos secrete histamine2, and that the interaction of histamine from the embryo helps the embryo implant into the endometrium of the uterus. But, there is also one study showing that anti-histamines decrease blood flow to the uterus. So while the research suggests that anti-histamines interfere with reproduction, we don’t have a clear answer. What can we do until we know more?

We can do the best with what we know now. We know that histamine is a naturally occurring molecule that may aid in implantation. We know that we may not want to hinder histamine. Therefore, while limiting use of anti-histamines when possible is reasonable, there is no evidence that anti-histamines make a difference on fertility or IVF outcomes.


  • Histamine enhances cytotrophoblast invasion by inducing intracellular calcium transients through the histamine type-1 receptor, Liu et al, Mol Reprod Dev 2004 Jul;68(3)345-53.
  • Identification of a histamine-releasing factor secreted by human pre-implantation embryos grown in vitro. Cocchiara et al, Journal of Reprod Immunology 1988 Jun;13(1):41-52
  • Effect of mepyramine, a histamineH1 and burimamide, a histamine H2 receptor antagonist, on ovum implantation in the rat. Brandon et al, J. Reprod. Fertil. 1977 July;50(2)251-4.
  • Implantation and deciduation process after the action of the antihistamine preparation diaprizin in early rat embryogenesis. Ontogenez 1981; 12(6) 596-604.


JenniferJennifer Agard, MD, Reproductive Endocrinology and Infertility Specialist. Dr. Agard completed her medical training at UCLA, Saint Barnabas Medical Cen-ter, and Eastern Virginia Medical Center. Her special interests are in polycystic ovarian syndrome, thyroid disease, therapeutic reproductive surgery, and di-minished ovarian reserve. Dr. Agard is committed to the model of delivering individualized patient-centric care. ??er greatest reward is being able to help create the family and life plan that is unique for each of us.