Can a pregnant woman in her first trimester take Montek LC (montelukast) for cold symptoms?

Safety of Montelukast (Montek LC) During First Trimester Pregnancy for Cold Symptoms

Montelukast can be used during the first trimester of pregnancy for cold symptoms if clearly needed, as it is a pregnancy category B medication with no evidence of increased risk of congenital malformations. 1, 2

Safety Profile of Montelukast in Pregnancy

• Montelukast is classified as FDA pregnancy category B, indicating animal studies have not demonstrated risk to the fetus and there are no adequate well-controlled studies in pregnant women 1
• The American Congress of Obstetricians and Gynecologists and American College of Allergy recommend montelukast can be considered during pregnancy, especially in patients who have shown favorable response prior to pregnancy 2
• Animal reproductive studies have shown no teratogenic effects at doses up to 100 times the maximum recommended human dose 1
• Montelukast crosses the placenta but has not been associated with increased risk of major malformations 1, 3

Evidence from Human Studies

• A prospective comparative study of 180 montelukast-exposed pregnancies found only one major malformation, which is within the baseline population risk of 1-3% 4
• A more recent two-center cohort study in Japan showed no significant difference in major congenital anomalies between montelukast-exposed pregnancies and controls (adjusted odds ratio 0.78) 3
• A Danish population-based study found no significant increase in congenital anomalies with montelukast exposure during pregnancy 5
• While some studies noted slightly lower birth weights in montelukast-exposed pregnancies, this was likely associated with the severity of maternal asthma rather than medication effects 4

Treatment Considerations for Cold Symptoms in First Trimester

• For cold symptoms during pregnancy, safer alternatives should be considered first 6:

  • Saline nasal rinses are considered first-line and safe during pregnancy 2
  • Topical nasal corticosteroids may be used safely if needed 2

• Important cautions for treating cold symptoms in pregnancy:

  • Oral decongestants should be avoided during the first trimester due to potential associations with gastroschisis and small intestinal atresia 2
  • First-generation antihistamines should be avoided due to their sedative and anticholinergic properties 2

Recommendations for Using Montelukast in First Trimester

• Montelukast should be used at the lowest effective dose when clearly needed 2, 1
• The manufacturer maintains a registry for pregnant women exposed to montelukast, and healthcare providers are encouraged to report prenatal exposures 1
• If the patient has previously responded well to montelukast, continuing it during pregnancy is reasonable 2
• Montelukast is excreted in breast milk (approximately 1%), but the benefits of breastfeeding are generally considered to outweigh potential risks 2

Algorithm for Decision Making

1. Assess severity of cold symptoms and impact on maternal well-being
2. Try non-pharmacological approaches first (hydration, rest, saline nasal rinses) 2
3. If additional treatment is needed, consider:
   • If patient was on montelukast before pregnancy with good response: continue 2
   • If initiating treatment: consider safer alternatives before starting montelukast 2
4. If montelukast is prescribed, use lowest effective dose and monitor for symptom improvement 1

Remember that maintaining maternal health is important for fetal well-being, and untreated severe symptoms can potentially cause more harm than medication use 2.