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Class ⬇

Respiratory (Leukotriene Receptor Antagonist)

PREGNANCY RECOMMENDATION:Human Data and Animal Data Suggest Low Risk

BREASTFEEDING RECOMMENDATION:Probably Compatible

Pregnancy Summary ⬆ ⬇

Numerous studies were located that describe the use of montelukast in human pregnancy. From a total of more than 1,250 first-trimester exposures, the prevalence rate of major malformations was 2.9%, and no pattern to the defects was seen. In addition, a recent 2024 review and meta-analysis also reported no significant increase in major birth defects with early pregnancy usage of montelukast. The drug will probably cross the placenta, so some fetal exposure will likely occur. Animal data did not show any embryofetal toxicity in two species at doses of more than 10 times the MRHD. While ACOG considers long-acting Beta-agonists as the preferred add-on controller therapy for asthma in pregnancy, leukotriene receptor antagonists, such as montelukast, may be used as alternative add-on therapies.

Breastfeeding Summary ⬆ ⬇

One report of seven lactating women was located that described the use of montelukast during human lactation. The drug was found in human breast milk with a peak concentration of about 10 ng/mL and a mean concentration of about 5.3 ng/mL. The calculated RID was less than 1%. Breastfeeding while using this drug should be based on the mother’s clinical need for treatment versus any potential infant risks that might occur. If used, the infant should be monitored for the most common reported adult side effects of headache and abdominal pain (both leading to irritability), fever, cough, diarrhea, and various infections.

Reference ⬆

  1. Prescribing Information. Montelukast. XLCare Pharmaceuticals; 2023.
  2. American College of Obstetricians and Gynecologists. Asthma in pregnancy: ACOG practice bulletin no. 90. Obstet Gynecol . 2008;111:457-464.
  3. BakhirevaLN, JonesKL, SchatzM, et al; the Organization of Teratology Information Specialists Collaborative Research Group. Safety of leukotriene receptor antagonists in pregnancy. J Allergy Clin Immunol . 2007;119:618-625.
  4. SarkarM, KorenG, KalraS, et al. Montelukast use during pregnancy: a multicentre, prospective, comparative study of infant outcomes. Eur J Clin Pharmacol . 2009;65:1259-1264.
  5. Cavero-CarbonellC, Vinkel-HansenA, Rabanque-HernandezMJ, et al. Fetal exposure to montelukast and congenital anomalies: a population based study in Denmark. Birth Defects Res . 2017;109:452-459.
  6. DattaP, Rewers-FelkinsK, BakerT, HaleTW. Transfer of montelukast into human milk during lactation. Breastfeed Med . 2017;12:54-57.
  7. HatakeyamaS, GotoM, YamamotoA, et al. The safety of pranlukast and montelukast during the first trimester of pregnancy: a prospective, two-centered cohort study in Japan. Congenit Anom (Kyoto) . 2022;62: 161-168.
  8. FareedA, SibliniD, VaidR, et al. Montelukast use in pregnancy: a systematic review and meta-analysis of maternal and fetal outcomes in asthma treatment. Congenit Anom (Kyoto) . 2024;64:220-227.