Abstract

In patients with rheumatic diseases, the well-documented benefits of breastfeeding must be carefully weighed against the risks of medication exposure to the infant. Given the absence of placebo controlled studies, estimation of drug safety is based on small studies of drug levels in breast milk and infant serum, case reports of adverse events in breastfed infants, and theoretical considerations.1 Medications are transferred to breast milk primarily via diffusion. Those with short half-lives, high protein binding, and/or high molecular weights are less likely to cross into breast milk.1 In general, breast milk drug levels of less than 10 % of the infant therapeutic dose or the maternal weight-adjusted dose are considered to be safe.2 Most medications have peak levels in breast milk 1-2 hours after maternal ingestion; avoiding nursing during this window may significantly reduce infant exposure.1 Table 1. Summary of safety data onthe use of anti-inflammatory and immunosuppressive medication in lactation