Is it possible to breast-feed after single or occasional doses of ondansetron (Zofran)?/nMothers wh

Fråga: Is it possible to breast-feed after single or occasional doses of ondansetron (Zofran)? Mothers who undergo caesarean section sometimes receive 1-3 doses of ondansetron iv for nausea.

Sammanfattning: No data on transfer of ondansetron to human breast milk has been found. Single or occasional doses of ondansetron during the day after a caesarean section to a mother of a healthy, full-term, infant would probably not result in any significant exposure to the nursing child. However, observation of the child is recommended.

Svar: A similar question has previously been answered in Drugline (1). The only information available was from Fass (the Swedish catalogue of approved medical products), where it is stated that ondansetron is excreted into breast milk in such amounts that a risk for the child exists even in therapeutic doses (1,2). However, this statement is based on animal studies in rats (1).

A thorough literature search in Drugline, Medline, Embase and common pharmacological handbooks as well as personal communication with the manufacturer (3) revealed no further information whether ondansetron, or any of the other setrons (granisteron or tropisetron), passes over to breast milk or not. However, the relatively low molecular weight (366 g/mol) of ondansetron makes it likely that it will pass over to breast milk (4).

The amount of milk a lactating child receives the first day after birth is quite small. The half-life of ondansetron is approximately three hours (5), and the oral bioavailibility is 60 percent (2). Therefore, the nursing child would probably not be exposed to any significant amounts after the mother has received single or occasional doses.