Treating allergic rhinitis in pregnancy. Safety considerations

Allergic rhinitis affects approximately one-third of women of childbearing age. As a result, symptoms ranging from sneezing and itching to severe nasal obstruction may require pharmacotherapy. However, product labels state that medications for allergic rhinitis should be avoided during pregnancy due to lack of fetal safety data, even though the majority of the agents have human data which refute these notions. We present a systematic and critical review of the medical literature on the use of pharmacotherapy for the management of allergic rhinitis during pregnancy. Electronic databases and other literature sources were searched to identify observational controlled studies focusing on the rate of fetal malformations in pregnant women exposed to agents used to treat allergic rhinitis and related diseases compared with controls. Immunotherapy and intranasal sodium cromoglycate (cromolyn) and beclomethasone would be considered as first-line therapy, both because of their lack of association with congenital abnormalities and their superior efficacy to other agents. First-generation (e.g. chlorpheniramine) and second-generation (e.g. cetirizine) antihistamines have not been incriminated as human teratogens. However, first-generation antihistamines are favoured over their second generation counterparts based on their longevity, leading to more conclusive evidence of safety. There are no controlled trials with loratadine and fexofenadine in human pregnancy. Oral, intranasal and ophthalmic decongestants (e.g. pseudoephedrine, phenylephrine and oxymetazoline, respectively) should be considered as second-line therapy, although further studies are needed to clarify their fetal safety. No human reproductive studies have been reported with the ophthalmic antihistamines ketorolac and levocabastine, although preliminary data reported suggest no association between pheniramine and congenital malformations. There are no documented epidemiological studies with intranasal corticosteroids (e.g. budesonide, fluticasone propionate, mometasone) during pregnancy; however, inhaled corticosteroids (e.g. beclomethasone) have not been incriminated as teratogens and are commonly used by pregnant women who have asthma. In summary, women with allergic rhinitis during pregnancy can be treated with a number of pharmacological agents without concern of untoward effects on their unborn child. Although the choice of agents in part should be based on evidence of fetal safety, issue of efficacy needs to be addressed in order to optimally manage this condition.