Iressa and Breastfeeding
Because of the potentially serious side effects associated with Iressa (gefitinib), the manufacturer of the drug recommends that women not breastfeed while taking it. Although it is unknown whether this drug passes through breast milk in humans, it is known to pass through breast milk in rats and may pass through human breast milk to some extent.
Iressa® (gefitinib) is a prescription medication used in the treatment of certain types of lung cancer. It is used in people who did not improve after treatment with certain other chemotherapy medicines.
At this time, it is unknown whether Iressa passes through breast milk in humans. The manufacturer of the medication recommends women not breastfeed during Iressa treatment.
In animal studies, the drug was shown to pass through breast milk when given to lactating rats in doses that were about one-fifth the equivalent of the recommended human dose. In these studies, the levels of Iressa were higher in the rat's milk than in the blood.
No research has been done to see if Iressa passes through breast milk in humans. However, based on the properties of the medication, it is expected to pass through human breast milk to some extent.
Iressa is associated with potentially serious side effects, including lung disease. Because the risk for Iressa side effects in a nursing child cannot be ruled out, it is probably safest to not breastfeed while using Iressa.
You should discuss breastfeeding and Iressa use with your healthcare provider. Each woman's situation is different, and you and your healthcare provider understand your situation best. After considering what you want and expect, as well as your current health situation, the two of you can make a shared decision that is right for you.