Do Nasal Allergies Worsen During Pregnancy, And How Should They Be Treated?

Women go through a number of important physiologic and immunologic changes during pregnancy. Blood volume and estrogen levels both increase during pregnancy, which frequently lead to mucous membrane swelling in the nose. For this reason, many women who have no history of rhinitis develop nasal congestion during pregnancy. Women with allergic rhinitis may develop worsening nasal symptoms while pregnant, although it has been estimated that roughly equal numbers of women experience an increase, reduction, or no change in their nasal allergic symptoms. In my own experience, the majority of women develop worsening symptoms while pregnant, usually consisting of nasal congestion.Treatment of allergic rhinitis during pregnancy must always consider the effect of the therapy upon the growing fetus.

Given the capacity of many medications to have potential effects upon fetal development, it is critical to determine what the woman is allergic to in order to set up a program of allergen avoidance measures. If the patient has not been previously allergy tested, I counsel against performing allergy skin testing because of the small but possible risk of a systemic reaction. Rather, it is preferable to do blood tests, which can serve as a sound basis for environmental control measures for house dust mites, animal danders, molds, and pollens. Despite avoiding relevant allergens, most women with significant nasal allergies will require some medication to successfully treat their symptoms.

The FDA has created a rating system that classifies all medicines approved since 1980 into five categories , referred to as A, B, C, D, and X. Category A is considered the safest, while category X medications are absolutely contraindicated under any circumstances. None of the medications used for allergic rhinitis are classified as category A, and the majority of drugs used for rhinitis fall into categories B and C. We always try to start with category B drugs, adding any required medications that are labeled category C. Keeping safety in mind, medications should be directed at specific symptoms. If sneezing, nasal discharge, and itching of the eyes and nose are the predominant symptoms, either intranasal cromolyn spray or oral antihistamines may be adequate. Nasal cromolyn, which is available over the counter, is not absorbed to any significant degree into the bloodstream and is therefore considered one of the safest allergy medications to take during pregnancy.

FDA Drug Ratings for Use in Pregnancy
Category Interpretation
A Adequate, well-controlled studies in pregnant women have not shown an increased risk of fetal abnormalities to the fetus in any trimester of pregnancy
B Animal studies have revealed no evidence of harm to the fetus; however, there are no adequate and well-controlled studies in pregnant women.
Animal studies have shown an adverse effect, but adequate and wellcontrolled studies in pregnant women have failed to demonstrate a risk to the fetus in any trimester.
C Animal studies have shown an adverse effect and there are no adequate and well-controlled studies in pregnant women.
No animal studies have been conducted and there are no adequate and well-controlled studies in pregnant women.
D Adequate well-controlled or observational studies in pregnant women have demonstrated a risk to the fetus. However, the benefits of therapy may outweigh the potential risk. For example, the drug may be acceptable if needed in a life-threatening situation or serious disease for which safer drugs cannot be used or are ineffective.
X Adequate well-controlled or observational studies in animals or pregnant women have demonstrated positive evidence of fetal abnormalities or risks. The use of the product is contraindicated in women who are or may become pregnant.

Loratadine and cetirizine are both category B medications, and loratadine is usually favored due to its longer record of use in pregnancy. Diphenhydramine and chlorpheniramine are older drugs that have been used extensively in pregnancy. However, both of these drugs cause significant sleepiness and fatigue and are not tolerated well by many patients. If nasal congestion presents as the most prominent symptom, as it often does during pregnancy, nasal steroids are indicated. Budesonide  (Rhinocort Aqua) is rated as category B, while  other intranasal steroids, including ciclesonide, fluticasone propionate, mometasone furoate, and triamcinolone acetonide, are category C.

Other drugs that are effective for nasal congestion include pseudoephedrine, which should be avoided during the first trimester because of an increased risk of infantile  gastroschisis (herniation of intestines outside of the body). If you become pregnant while taking allergy shots, the shots can be continued at whatever dose is currently being given and should not be increased until after the baby is delivered because of concerns regarding systemic reactions. For this same reason, allergy shots should not be initiated during pregnancy. If you are pregnant and have questions regarding allergy shots and allergy medications, you should consult with your treating physicians.

Your obstetrician, primary care doctor, and possibly a consulting allergist may all provide guidance regarding these treatment issues. It is best not to stop or alter your treatment regimen unless you have discussed potential changes with them.

Jacquelyn’s comment:

I had really mild allergies for most of my life, and when I became pregnant, things changed quickly. The first thing I noticed was that I couldn’t breathe through my nose at night because of stuffiness, and then I started to have a postnasal drip that wouldn’t go away. My obgyn doctor gave me Benadryl to take at night. It made the drip really thick, and my nose was still quite blocked up. Besides that, I was so sleepy that I couldn’t get up in the morning. I got Claritin after that, which didn’t make me sleepy but wasn’t any more effective than the Benadryl. I saw an allergist, who prescribed Rhinocort twice a day, and after a few days my nose finally opened up enough so I could sleep at night. He assured me that it was safe during pregnancy.