Anthracycline and related cytostatic antibiotics, whether used as monotherapy or in combination with other antineoplastics, are contra-indicated in breastfeeding because of their cytotoxic action on dividing cells and their varied and high toxicity in normal therapeutic use. There is a high risk of bone marrow depression and other adverse effects in the breastfed infant.
The risks associated with their use will be additive with other antineoplastic agents with which they are normally used in combination.
In most cases it will not be possible to suggest a safer alternative. Choice of drug will depend on a number of disease and treatment protocol parameters.
There is no evidence-based, definitive time period after treatment when breastfeeding can be safely resumed, especially when drugs are used in combination. Therefore, if use of an anthracycline is deemed clinically necessary, breastfeeding should be discontinued.