Etanercept

It is a fusion protein that inhibits tumour necrosis factor alpha (TNFα); it is used to treat autoimmune diseases such as rheumatoid arthritis, psoriatic arthritis, psoriasis and ankylosing spondylitis.. Subcutaneous administration once or twice a week for 12 to 24 weeks.

Possibly due to its high molecular weight and its high plasma protein binding, it is excreted in breastmilk in clinically insignificant amounts. ^{(Bertrand 2023, Butler 2014, Berthelsen 2010, Keeling 2010, Murashima 2009, Østensen 2007, 2006 and 2004)}

The plasma levels of infants breastfed by mothers who are administered etanercept are undetectable or very low. ^{(Berthelsen 2010, Keeling 2010, Murashima 2009).}

No short-term or long-term developmental, infection or immunological problems or problems with vaccination have been observed in infants whose mothers take etanercept. ^{(Bertrand 2023, Membrive 2023, Dall'ara 2016, Calligaro 2015, Butler 2014, Keeling 2010)}, with the exception of one case involving a 3-month-old infant who developed drowsiness, feeding difficulties and hypotonia one week after his mother, who had ankylosing spondylitis, began treatment with etanercept. Breastfeeding continued until the infant was 5 months old. ^{(Eskiyurt 2026)}

Its zero oral bioavailability would hinder transfer from breastmilk to the infant’s plasma ^{(Amin 2018, Grunewald 2015, Mervic 2014, Butler 2014, Hyrich 2013, Bae 2012, Keeling 2010)}, except in premature infants and the immediate neonatal period, when there can be greater intestinal permeability. Waiting two weeks after giving birth before resuming treatment allows the newborn’s plasma levels to fall from their pre-birth levels and also minimises transmission to the baby. ^{(Krysko 2023)} 

TNF-alpha plays a role in milk production, which may explain why several anti-TNF drugs, such as adalimumab, infliximab, golimumab, certolizumab and etanercept, may increase the risk of lactation failure. ^{(Yan 2026)}

Many experts and scientific societies in the fields of rheumatology and dermatology consider its use during breastfeeding to be very low-risk and, therefore, safe. ^{(Rüegg 2025, Russell 2023, Sammaritano 2020, Amin 2018, Flint 2016, Götestam 2016, Dall'ara 2016, Grunewald 2015, Witzel 2014, Nielsen 2014, Mervic 2014, Butler 2014, Hyrich 2013, Habal 2012, Berthelsen 2010, Keeling 2010, Fischer 2010, Murashima 2009)}

See below the information of this related product:

• Maternal Rheumatoid arthritis (RA) (Fairly safe. Mild or unlikely adverse effects. Compatible under certain circumstances. Follow-up recommended. Read Commentary.)