Medications and Lactation: What PNPs Need to Know

Jennifer M. Marks, BS; Diane L. Spatz, PhD, RNC

J Pediatr Health Care 17(6):311-317, 2003.

Abstract and Introduction

The current rise in breastfeeding rates coincides with a continuously expanding prescription medication market. Now more than ever, pediatric nurse practitioners (PNP) are responsible for ordering and consulting on maternal medications during lactation. PNPs are obligated to determine the safety of medications by critically reviewing recommendations that are based on recent clinical research. However, sources vary widely in the relevance of their information. Ideally, comprehensive research-based recommendations about medications and lactation should be based on the pharmacokinetics of drugs in the maternal system, the oral bioavailability of the medication to the infant, and the infant evaluation. Review of the data enables PNPs to effectively evaluate drugs and their actual risks to a breastfeeding infant, thereby supporting integration of sound evidence-based care into clinical practice.

Extensive research, especially in recent years, has documented the uniquely superior properties of human milk and its advantages to infants, mothers, families, and society in health, nutritional, immunologic, developmental, psychological, social, economic, and environmental ways (American Academy of Pediatrics, 1997). For this reason, key groups have developed objectives and support or position statements on breastfeeding. The Department of Health and Human Services’ Healthy People 2010 set a target rate for breastfeeding of 75% in the immediate postpartum period and 50% at age 6 months (2000). The American Academy of Pediatrics recommends that infants be exclusively breastfed for 6 months and that breastfeeding continue for at least 12 months, and thereafter for as long as desired (1997). The National Association of Pediatric Nurse Practitioners (NAPNAP) identifies human milk as the preferred and superior form of infant nutrition and, therefore, encourages pediatric nurse practitioners (PNPs) to implement anticipatory guidance and clinical assistance as a means for increasing national breastfeeding initiation and duration rates (NAPNAP, 2001).

Because of the wide endorsement of breastfeeding in both the health care and lay communities, more mothers are committed to breastfeeding their children. Too often, however, care provided to lactating mothers and their breastfeeding newborns lacks evidence supportive of the techniques used or care provided. Thus, health care professionals can be ineffective because they provide women with inconsistent, inaccurate, and/or inadequate breastfeeding information and recommendations (Humenick, Hill, & Spiegelberg, 1998). This substandard advice generally results from a weak knowledge base rather than negative attitudes toward breastfeeding (Goldstein & Freed, 1993). In a survey of 134 pediatric office nurses, including several PNPs, 83% agreed that breastfeeding promotion was a good use of their time and 79% agreed that follow-up of a newly nursing mother was the role of an office nurse (Register, Eren, Lowedermilk, Hammond, & Tully, 2000). However, clinical advice often included inappropriate recommendations for initiating formula supplementation and normal or abnormal feeding patterns for a breastfed infant (Register, et al., 2000). Nursing students have reported that their breastfeeding instruction consisted mainly of didactic lecture (Freed, Clark, Harris, Lowdermilk, 1996), and fewer than half of the pediatric nurses in Register et al.’s study identified their nursing school as a source of breastfeeding training. In addition, Register et al. found that fewer than half of these pediatric nurses felt very confident or confident in working with a breastfeeding mother with concerns about adequate milk supply (46%), adequate infant weight gain (45%), or medications that the mother was taking (43%).

Because the pediatric clinic is the first place that the mother-infant unit has contact with health care workers after hospital discharge, and because many women depend on PNPs for help with their breastfeeding concerns and advice, these findings have negative consequences for new mothers. Moreover, practitioner responsibility dictates that daily decisions be made that have profound effects on nursing infants through the ordering of, and consultation on, maternal medications. Too often, breastfeeding mothers are erroneously advised by their practitioners to discontinue breastfeeding for the duration of maternal use of a prescribed medication (Riordan & Auerbach, 1998). This recommendation is usually unjustified and reflects a lack of knowledge regarding medications and lactation (Banta-Wright, 1997). If a nursing mother were to follow this advice, her infant could have an increased risk for viral infections and serious conditions such as necrotizing enterocolitis and chronic digestive diseases, because infant formula does not provide protection against viruses or pathogenic bacterial organisms (AAP, 1997; Auerbach, 1999). Because of the extensive benefits of breast milk, breastfeeding in the majority of cases far outweighs potential risks. Ethically, practitioners can no longer hide behind the notion that it is easier and less threatening to recommend weaning than it is to look into the situation and be assured that a particular medication poses little or no danger to the infant (Riordan & Auerbach, 1998). Basing lactation advice on documented evidence is the first step in acknowledging that breastfeeding care is not simply a personal lifestyle choice but also a health care behavior deserving of both scientific study and informed clinical assistance (Auerbach, 2000).

In accordance with evidence-based practice, before breastfeeding cessation is considered for maternal medication therapy, adequate information should be sought and the healthcare provider should consider the risk of the drug versus the benefit of breastfeeding for the infant (Lawrence, 1997). While the majority of medications pass into breast milk, most have no effect on maternal milk supply or on infant well-being when they are taken by breastfeeding women in therapeutic dosages (AAP, 2001). With rare exception, the concentrations of medications most likely to be prescribed to breastfeeding mothers are exceedingly low in breast milk and the dose delivered to the breastfed infant is most often subclinical (Hale, 2002). Therefore, in reality, very few drugs are contraindicated during lactation. If a concern arises, the number of drug preparations available usually offers numerous suitable medication alternatives. Knowledge of the pharmacokinetics of the drug in the maternal system and the absorption, distribution, metabolism, storage, and elimination of the medication by the recipient infant can be helpful in identifying the relative risk of giving a breastfeeding mother a medication (Lawrence, 1997). Therefore, comprehensive, research-based recommendations about the use of medications during lactation should be based on the following determinants of drug transfer into breast milk: maternal plasma concentrations, lipid solubility of the drug and fat content of milk, milk pH, half-life of the drug, molecular weight of the drug, and protein binding of the drug in maternal plasma (Hale, 2002). Furthermore, recommendations must take into account the oral bioavailability of the specific medication by an infant and the comprehensive clinical evaluation of the infant’s ability to tolerate exposure to the maternal medication in question (Hale, 2002). These parameters taken together enable PNPs to effectively evaluate drugs and to create the most comprehensive estimates available of the actual overall risk to the infant from maternally ingested medications.

A cikk teljes szövege itt olvasható. (A hozzáféréshez regisztrálni kell a Medscape oldalán!)