Tab Montek-LC 5 (Montelukast + Levocetirizine) and Tab Prednisolone 10 mg in Lactation

Montelukast (component of Montek-LC)

• Montelukast has low bioavailability and is "most likely compatible" with lactation according to dermatology/pulmonology references (Dermatology 2-Vol Set; Fishman's Pulmonary Diseases).
• The main caution isn't infant toxicity but a theoretical reduction in milk supply, since montelukast can lower prolactin levels. Use should be minimized to what's clinically necessary, per AAFP guidance on allergic rhinitis in breastfeeding.

Levocetirizine (component of Montek-LC)

• It's a second-generation antihistamine (active enantiomer of cetirizine) with low milk transfer and no sedative effects reported in infants at usual doses (Fitzpatrick's Dermatology).
• Like other second-generation antihistamines, it may theoretically reduce milk supply via mild anticholinergic effect, but this is a much smaller concern than with first-generation antihistamines (diphenhydramine, promethazine).

Prednisolone 10 mg

• This is well studied and favorable. Multiple sources agree:
  • Prednisolone (and prednisone, its inactive prodrug) appear in breast milk only in very low concentrations - LactMed and Rheumatology textbook note the American Academy of Pediatrics considers it compatible with breastfeeding even at doses above 20-40 mg/day.
  • At a 10 mg dose, peak milk levels are very low (~28 mcg/L), representing a tiny fraction of infant exposure.
  • No adverse effects have been reported in breastfed infants of mothers taking prednisolone, including case reports of prednisolone 5-7.5 mg/day and prednisone 10 mg/day used long-term.
  • The old advice to wait 4 hours after a dose before nursing is not actually necessary given how low milk levels are, though some clinicians still suggest it for higher doses (over 20 mg/day) out of caution.
  • Medium-to-large doses (not 10 mg) can occasionally cause a temporary reduction in milk supply.

Practical takeaway

• At the doses you mentioned (Montek-LC 5, Prednisolone 10 mg), both are considered low-risk / compatible with breastfeeding based on standard references (LactMed, AAP, Breastfeeding Network, and the textbook sources above).
• If you want to be extra cautious with the prednisolone, taking it right after a feed (rather than right before) minimizes the small amount transferred, though this isn't strictly required at 10 mg.
• Watch for reduced milk supply as the main practical side effect to monitor with either drug, and use for the shortest effective duration.