Pharmacology Review

Objectives

After completing this article, readers should be able to:

1. Describe the transfer of various medications into human milk.

2. Describe the hazards, if any, of administering medications to breastfeeding mothers.

3. Describe the treatment of various syndromes with medications most suitable for breastfeeding mothers.

Introduction

Human milk not only is perfect nutrition for human infants, but it also provides an enormous array of growth factors and, most importantly, immunoglobulins that protect the infant from infectious disease during the first year after birth. Human milk is perfectly suited for the infant’s gastrointestinal (GI) tract, with the numerous growth factors enhancing growth and maturation of a relatively permeable GI tract and the high concentration of immunoglobulins directly protecting the GI tract from infectious organisms. Ultimately, infectious disease and mortality are significantly reduced in breastfed infants.

Although recent studies clearly have suggested that the number of women who choose to breastfeed is rising, the number of women who discontinue breastfeeding to take a medication because of advice from their clinicians is too high. Surveys in western countries indicate that 90% to 99% of women who breastfeed receive at least one medication during the first week postpartum. In at least one study, the use of medications was one of the major reasons that women discontinued breastfeeding.

Generally, some medication penetrates the milk compartment and exposes most infants to some medication, albeit in low concentrations. The degree of risk almost always is a function of the type (and risks) of medication being used and the dose transferred to the infant. Fortunately, for most medications, the dose transferred to the infant and the subsequent risk is low to nil. However, the clinician always must evaluate individual cases with respect to the medication used, the dose of medication transferred, and the relative ability of the infant to maintain homeostasis while …