Deskast (Montelukast) Safety in Pregnancy
Montelukast can be continued during pregnancy if the patient has demonstrated a favorable response for recalcitrant asthma, but should be avoided for chronic rhinosinusitis or other non-asthma indications where efficacy is unproven.
Primary Recommendation for Asthma Management
Montelukast (Deskast) is FDA Pregnancy Category B, meaning animal studies have not demonstrated fetal risk, though controlled studies in pregnant women are lacking 1.
The American Congress of Obstetricians and Gynecologists recommends montelukast can be considered for recalcitrant asthma during pregnancy, specifically in patients who have shown a favorable response prior to pregnancy 1.
The drug manufacturer maintains a pregnancy registry for patients exposed to montelukast during pregnancy, reflecting ongoing safety monitoring 1.
When to Avoid Montelukast
Anti-leukotrienes should be avoided for chronic rhinosinusitis (CRS) maintenance during pregnancy due to lack of efficacy data in CRS and limited teratogenicity data 1.
For non-asthma indications where montelukast efficacy is questionable, the risk-benefit calculation does not favor use given the absence of controlled safety studies 1.
Clinical Decision Algorithm
For patients currently on montelukast:
- If used for asthma with documented prior response → Continue therapy 1
- If used for chronic rhinosinusitis or allergic rhinitis → Discontinue and use safer alternatives (saline rinses, topical corticosteroid nasal sprays) 1
For initiating new therapy:
- Asthma requiring escalation → Can initiate if other therapies inadequate 1
- Any other indication → Do not initiate; use pregnancy-safe alternatives 1
Breastfeeding Considerations
Montelukast is excreted in breast milk, though extensive metabolism and plasma protein binding limit infant exposure to approximately 1% of the maternal dose 1.
The benefits of breastfeeding overwhelm the risk of exposure in most cases 1.
To further minimize infant exposure, breastfeed prior to taking the medication 1.
Important Caveats
The recommendation prioritizes maternal asthma control, as poorly controlled asthma poses greater fetal risks than montelukast exposure 1.
No human teratogenicity has been demonstrated in animal studies, but the absence of controlled human trials means theoretical risks cannot be completely excluded 1, 2.
All medication decisions during pregnancy require balancing symptom severity against potential fetal exposure, with montelukast representing a reasonable option when asthma control justifies its use 1, 3.