Reviewer: S. Randhawa, M.D., Allergist/Immunologist and Assistant Professor at NSU
A 27-year-old Caucasian female is seen for a follow-up of allergic rhinitis and asthma. She is on immunotherapy (grasses, trees, ragweed, weeds, cat, dust mite), started one year ago. She stopped using Advair on her own 6 months ago and currently reports symptoms of asthma 2 times per week which are partially relieved by a rescue inhaler use. She has had no nighttime symptoms and no emergency room visits in the past year. She reports symptoms of allergic rhinitis, although since she started immunotherapy, the symptoms are mostly seasonal, limited to runny nose in the fall.
She has been trying to become pregnant for the last 2 months and wants to know if any medication changes may be needed.
Past medical history (PMH)
Asthma, allergic rhinitis
Medications
Dallergy b.i.d. for three days around the time of each allergy shot. She receives the immunotherapy every week. Fluticasone, nasal spray. She also takes a prenatal multivitamin daily and she stopped using Advair (fluticasone/salmeterol) 6 months ago.
Physical examination
Well-developed, well nourished in no apparent distress. Vital signs: Temperature 98.5, pulse 81, respiratory rate 12, blood pressure 120/60. Skin: No rash. Ears: Normal. Nose: Boggy, paleturbinates. Ears: Normal. Chest: Clear to auscultation bilaterally. Cardiovascular: Clear S1, S2. Extremities: No edema or clubbing.
Procedures
Spirometry shows FVC of 100%, FEV1 of 89% and FEV1/FVC of 0.79. Her ACT score is 18/25.
Would you change this patient's medications for allergic rhinitis?
In light of the fact that she is trying to become pregnant, we recommended a category B intranasal steroid -- Rhinocort Aqua (budesonide) one spray daily.
We also advised her against using medications such as Allegra (fexofenadine) or Dallergy (chlorpheniramine, phenylephrine, and methscopolamine), which may have an adverse affect on the fetus.
We recommended Zyrtec (cetirizine) prn whenever she has symptoms because Zyrtec is pregnancy category B.
Antihistamines are frequently needed by pregnant women for the treatment of allergic disorders. Most second generation antihistamines carry a Pregnancy B rating but, for example, Allegra (fexofenadine) is Category C (Probably Safe).
Most intranasal steroids (INS) have a pregnancy C rating. The achievement of a Category B rating indicates that adequate studies in pregnant women have demonstrated that treatment does not increase the risk of congenital malformations to the fetus during the first trimester of pregnancy and in later trimesters.
Would you change this patient's asthma medications?
Fluticasone is pregnancy category C. Inhaled budesonide (category B) was prescribed.
Mnemonic for inhaled steroids or INS use during pregnancy:
Corticosteroids (most)
C category during pregnancy
Budesonide
B category during pregnancy
Oral steroids and most inhaled steroids are also Category C.
Can immunotherapy be continued if the patient is on it and becomes pregnant?
Yes, immunotherapy can be continued at the maintenance dose. There should not be a dose escalation during pregnancy.
The immunotherapy dose should not be increased in a pregnant patient until after delivery.
What happens when the immunotherapy extract expires during pregnancy and a new vial has to be used?
When a new vial is used, there is generally a "step down" in the immunotherapy dose. Whether the allergist proceeds to "build up" to the previously used maintenance dose or stays at the lower dose is a matter of debate. Many allergists are more cautious and do not escalate the dose during pregnancy.
Can immunotherapy be started if a patient is pregnant or planning to become pregnant?
No. It is generally not recommended to start immunotherapy if a patient is pregnant or planning to become pregnant.
A systemic reaction occurring during pregnancy may produce severe fetal hypoxia or precipitate premature uterine contractions, therefore immunotherapy should not be initiated during pregnancy.
Pregnancy is not a true contraindication for immunotherapy, but by custom, immunotherapy is not initiated until after delivery.
Sublingual immunotherapy is safe during pregnancy, it is also safe when initiated for the first time in pregnancy (study) (Allergy, 2012).
What did we learn from this case?
Asthma is the most common chronic respiratory disease, affecting up to 10% of adults and 30% of children (JACI, 2011).
In pregnant patients or in patients trying to conceive who have allergic diseases, physicians should prescribe medications which are rated category B whenever possible.
Examples of pregnancy category B medications:
- inhaled steroids: budesonide (Pulmicort)
- intranasal steroids: budesonide (Rhinocort Aqua)
- antihistamines: loratidine and cetirizine
Treatment Options for Allergic Rhinitis (click to enlarge the image).
References
Managing asthma during pregnancy: recommendations for pharmacologic treatment. National Asthma Education and Prevention Program. Bethesda (MD): National Heart, Lung, and Blood Institute; 2005 Jan.
Antihistamine use during pregnancy. AAAAI.
Safety of AR Drug Classes During Pregnancy Antihistamines. Medscape.
Treating Asthma and Comorbid Allergic Rhinitis in Pregnancy: A Review of the Current Guidelines. Barbara Yawn, MD, MSc, FAAFP; Mary Knudtson, DNSc, NP
Medscape, 06/2007.
Which antihistamine or inhaled/intranasal steroid to use during pregnancy? Allergy Notes.
Birth defects after maternal exposure to corticosteroids: Prospective cohort study and meta-analysis of epidemiological studies. Teratology, Volume 62 Issue 6, Pages 385 - 392.
Allergen Immunotherapy. AFP, 2004.
Allergy Immunotherapy for Primary Care Physicians. J . Stokes , T . Casale. The American Journal of Medicine , Volume 119 , Issue 10 , Pages 820 - 823 (2006). Link via MDConsult.
Use of Immunotherapy in a Primary Care Office. AFP, 1998.
Asthma in Pregnancy. NEJM, 04/2009.
Asthma and pregnancy. JACI, 2011.
Rhinitis is common in asthma and impairs asthma control. Allergy. 2011.
Asthma exacerbations during pregnancy can be reduced with a FENO-based treatment algorithm - number needed to treat was 6 (Lancet, 2011).
Published: 10/02/2008
Updated: 03/29/2012
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