Treatment of allergic rhinitis in pregnancy

rhinitis

This article is mainly intedend for use by medical professionals.

Allergic rhinitis (AR) affects 20-30% of women in the childbearing age group with an annually increasing prevalence.

The classical clinical symptoms include sneezing, itching, nasal blockage, and nasal discharge. In patients who had allergic rhinitis before, the symptoms may worsen, improve or remain the same during pregnancy.

Rhinitis of Pregnancy

Many pregnant mothers notice some kind of nasal obstruction towards the last part of pregnancy which is termed as rhinitis of pregnancy. 

Rhinitis of pregnancy is a clinical condition in pregnant women, characterized by persistent nasal congestion and rhinorrhea for 6 weeks without any shreds of evidence of respiratory infection or history of rhinitis.

The exact cause for this rhinitis in pregnancy is unknown and is suspected to be due to hormonal variations. This usually occurs after the second trimester (6th month) and resolves itself after delivery.

Rhinitis of pregnancy usually doesn’t respond to anti-allergic medications, but intranasal steroid sprays can be prescribed as a trial.

Management of allergic rhinitis in pregnancy

As a general rule, a pregnant mother should avoid most of her medications, or use the lowest possible dose of medications to control her symptoms in pregnancy. All medications the mother is on needs to be reviewed once she is found to be pregnant.

The initial management of allergic rhinitis is to avoid exposure to allergens. This includes closing the windows, usage of sunglasses or masks, limiting outdoor exposure when pollen levels are high, avoiding exposure to animal dandruff, etc.

If the mother is having only mild symptoms, not affecting her quality of life adversely, then she can use saline nasal drops or nasal washing as advised by her doctor.

Drug therapy is recommended when avoidance of allergens is not possible or when avoidance measures fail to control symptoms.

Medical management of rhinitis in pregnancy

If medications are needed in pregnancy, selection of anti-allergic medications should be based on the US Food and Drug Administration (FDA) risk categories.

  • Category A – Adequate and well-controlled studies have failed to demonstrate a risk to the fetus in the first trimester of pregnancy (and there is no evidence of risk in later trimesters).
  • Category B – Animal reproduction studies have failed to demonstrate a risk to the fetus and there are no adequate and well-controlled studies in pregnant women.
  • Category C – Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant the use of the drug in pregnant women despite potential risks.
  • Category D – There is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience or studies in humans, but potential benefits may warrant the use of the drug in pregnant women despite potential risks.
  • Category X – Studies in animals or humans have demonstrated fetal abnormalities and/or there is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience, and the risks involved in the use of the drug in pregnant women clearly outweigh potential benefits.

Category A and B drugs are considered to be safe, while category D and X are avoided during pregnancy. Category C drugs should be judiciously used in pregnant women.

As of today, there exists no category A anti-allergic medications. Most of the medications belong to group B or C.

Intranasal steroids (INS)

INS also called as corticosteroid nasal sprays are considered to be the most effective drug (drug of choice) in treatment of allergic rhinitis.

They include various formulations like – Fluticasone, Mometasone, Budesonide, Flunisolide, and Triamcinolone. Though guidelines consider all these as safe during pregnancy, all these drugs except budesonide belong to category C, while Budesonide is the only category B drug. If not budesonide, the least absorbed medications like mometasone or fluticasone is considered to be the alternatives in pregnant ladies with rhinitis.

“Because studies in humans cannot rule out the possibility of harm, Budesonide should be used in pregnancy only if clearly indicated.”

However, Intranasal triamcinolone has been found to have a significant association with respiratory tract defects like choanal atresia.

A recent review of literature by Alhussein et al made the following conclusion.

Intranasal use of fluticasone furoate, mometasone, and budesonide is safe in pregnancy, if they are used at the recommended therapeutic dose after a proper medical evaluation. Intranasal fluticasone propionate might be a safe option in the absence of other INCS options due to its questionable efficacy during pregnancy. Risk-benefit ratio should always be considered before prescribing any intranasal corticosteroid sprays during pregnancy.

Intranasal antihistamines

Azelastine is the most commonly used intranasal antihistamine. But it is found to be associated with minor adverse effects in animal fetus and its safety data for humans are not available.

Generally, the use of intranasal antihistamines during pregnancy is not recommended.

Oral antihistamines

First-generation antihistamines like diphenhydramine are associated with the development of cleft palate in the fetus and is not recommended.

Second-generation antihistamines labeled as category B (cetirizine, loratadine) are preferred over first-generation in pregnant and nonpregnant individuals.

Third generation antihistamines like fexofenadine and desloratadine are associated with low birth weight in animal models and are currently categorized as C.

Oral decongestants

Use of oral decongestants during pregnancy is found to be associated with small intestinal atresia and development of gastroschisis (abdominal wall birth defect) in newborns. Hence, they are not recommended in pregnancy.

Leukotriene antagonists

Drugs like Montelukast, Zafirlukast are considered to be safe during pregnancy. But Zileuton, a 5-lipoxygenase inhibitor is contraindicated during pregnancy.

Immunotherapy in pregnancy

Immunotherapy for allergy should not be started during pregnancy because of the fear of anaphylactic reaction. But if the mother is already on immunotherapy, then the treatment can be continued throughout the pregnancy without increasing the dosage.

Home remedies for allergic rhinitis treatment

  • Avoid allergen triggers – like nasal allergens, pollutants, such as smog and cigarette smoke.
  • Use saline nasal sprays – can be a homemade nasal douching solution or over the counter preparations.
  • Take frequent steam inhalations – no need of adding any special ingredients.
  • Increase your physical activities and exercises.
  • Keep the head end of bed elevated by 30 to 45 degrees.

Conclusions

  • Allergic rhinitis affects one-third of pregnant ladies. Symptoms of pre-existing rhinitis can improve, worsen or can remain the same during pregnancy.
  • Avoidance of allergen should be the first line and is the best management option in the treatment of such patients.
  • Medical therapy can be considered when the quality of life is affected significantly. No medication is found to be absolutely safe in pregnancy.
  • Before considering any medication during pregnancy, it is important to weigh the severity of patient symptoms against the possible risks to the baby.
  • Topical drugs are suggested as a first approach.
  • Intranasal steroid spray is the drug of choice for allergy during pregnancy. Budesonide is the safest molecule, followed by Fluticasone and Mometasone.
  • Other anti-allergic medicines that can be considered in pregnancy are second-generation antihistamine like Cetrizine, leukotriene antagonists like Montelukast, Zafirlukast etc.

References

  1. Alhussien AH, Alhedaithy RA, Alsaleh SA. Safety of intranasal corticosteroid sprays during pregnancy: an updated review. European Archives of Oto-Rhino-Laryngology. 2017 Nov 21:1-9.
  2. Gonzalez-Estrada A, Geraci SA. Allergy Medications During Pregnancy. The American journal of the medical sciences. 2016 Sep 1;352(3):326-31.
  3. Intranasal triamcinolone use during pregnancy and the risk of adverse pregnancy outcomes.AU Bérard A, Sheehy O, Kurzinger ML, Juhaeri J SO J Allergy Clin Immunol. 2016 Jul;138(1):97-104.e7. Epub 2016 Apr 1.
  4. Ridolo E, Caminati M, Martignago I, Melli V, Salvottini C, Rossi O, Dama A, Schiappoli M, Bovo C, Incorvaia C, Senna G. Allergic rhinitis: pharmacotherapy in pregnancy and old age. Expert review of clinical pharmacology. 2016 Aug 2;9(8):1081-9.