Answer
It is unknown whether guselkumab (Tremfya) passes into human milk; human IgGs enter milk during the first days after birth and then decrease, so infant risk during this period cannot be excluded, and discontinuing breast-feeding or abstaining from therapy requires weighing benefits for the child and woman.
Sources for this answer
- Tremfya 100 mg OnePress solution for injection in pre-filled penJanssen-Cilag Ltd (a Johnson & Johnson Company) · emc · SmPC §4.6 Fertility, pregnancy and lactation · Version 16Document updated
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