What is the safest intranasal corticosteroid (INCS) to use during pregnancy?

Safest Intranasal Corticosteroid in Pregnancy

Intranasal budesonide is the safest first-line choice when initiating intranasal corticosteroid therapy during pregnancy, based on its FDA Pregnancy Category B classification and the most extensive human safety data among all available agents. 1

Clinical Decision Algorithm

If Already Using an INCS Before Pregnancy

• Continue your current intranasal corticosteroid without interruption, regardless of which agent you were using (fluticasone, mometasone, budesonide, or beclomethasone). 1
• No substantial difference in efficacy or safety exists among available intranasal corticosteroids, making switching unnecessary and potentially disruptive to symptom control. 1
• Discontinuing effective therapy can significantly worsen quality of life and potentially exacerbate comorbid conditions like asthma, which poses greater fetal risk than continuing the medication. 2

If Starting INCS Therapy During Pregnancy

• Initiate intranasal budesonide as first-line therapy due to its Pregnancy Category B status and extensive human safety data from over 6,600 pregnancies. 1, 3, 4
• Alternative safe options at recommended doses include mometasone and fluticasone propionate, both with reassuring safety profiles despite Category C classification. 1, 2, 5
• Beclomethasone also demonstrates no convincing evidence of congenital defects and may be used. 1

Evidence Supporting Safety

Meta-Analysis and Large-Scale Data

• A comprehensive meta-analysis found no increased risk of major malformations, preterm delivery, low birth weight, or pregnancy-induced hypertension with intranasal corticosteroid use during pregnancy. 1, 2
• Swedish registry data covering 2,534 infants exposed to inhaled budesonide in early pregnancy showed congenital malformation rates identical to the general population (3.6% vs. 3.5%). 3, 4
• The rate of orofacial clefts was not elevated (4 observed vs. 3.3 expected). 3, 4

Systemic Absorption Considerations

• Intranasal corticosteroids have negligible systemic absorption compared to oral formulations, making extrapolation from inhaled corticosteroid safety data reasonable and conservative. 1, 2
• Pharmacologic studies demonstrate much lower systemic exposure after intranasal versus oral administration. 1, 4

Dosing Strategy

• Use the lowest effective dose that adequately controls symptoms throughout all trimesters. 1, 6, 7
• Do not exceed manufacturer-recommended maximum daily doses. 2
• Taper to the minimum dose needed for symptom control rather than discontinuing therapy. 1

Ranking of INCS by Safety Data

Agent	Pregnancy Category	Safety Evidence Quality
Budesonide	B	Most extensive (>6,600 pregnancies) [1,3,4]
Mometasone	C	Explicitly listed as safe by expert panels [1,2,6,7]
Fluticasone propionate	C	Substantial accumulated data [1,2]
Beclomethasone	C	No convincing evidence of defects [1]
Fluticasone furoate	C	Limited but reassuring data [5]
Triamcinolone	C	Very limited data [1]

Critical Distinctions and Pitfalls

Do NOT Confuse with Oral Corticosteroids

• Oral corticosteroids carry substantially different and more serious risks, especially during the first trimester, including:
  • Increased risk of cleft lip with or without cleft palate 1, 2
  • Preeclampsia 1, 2
  • Preterm delivery and low birth weight 1, 2
  • Gestational diabetes and hyperglycemia 1, 7
• Intranasal formulations have negligible systemic effects compared to oral agents. 1, 2

Medications to Avoid

• Oral decongestants (pseudoephedrine, phenylephrine) should be avoided in the first trimester due to association with increased congenital malformations including gastroschisis. 1, 2
• Intranasal triamcinolone has been associated with respiratory tract defects in one study and should be avoided when alternatives exist. 5

Special Considerations

Asthma Comorbidity

• Treating rhinitis during pregnancy is particularly important in women with asthma, as uncontrolled rhinitis can trigger or worsen asthma symptoms, which poses greater fetal risk than medication exposure. 8
• Poorly controlled asthma increases risk of preeclampsia, prematurity, low birth weight, and small-for-gestational-age infants. 3, 8

Consultation Recommendations

• Consult with the patient's obstetrician when initiating therapy, particularly in complex cases or when considering oral corticosteroids after the first trimester. 1, 6
• Discuss benefits and risks with the patient to ensure informed decision-making. 1

Breastfeeding

• Intranasal corticosteroids are considered compatible with breastfeeding due to minimal systemic absorption. 2