Use of cough and cold preparations during breastfeeding

Breastfeeding, pregnancy, medicines, neurodevelopment, and population databases: the information desert

Background

The pharmacoepidemiology of the long-term benefits and harms of medicines in pregnancy and breastfeeding has received little attention. The impact of maternal medicines on children is increasingly recognised as a source of avoidable harm. The focus of attention has expanded from congenital anomalies to include less visible, but equally important, outcomes, including cognition, neurodevelopmental disorders, educational performance, and childhood ill-health. Breastfeeding, whether as a source of medicine exposure, a mitigator of adverse effects or as an outcome, has been all but ignored in pharmacoepidemiology and pharmacovigilance: a significant ‘blind spot’.

Whole-population data on breastfeeding: why we need them

Optimal child development and maternal health necessitate breastfeeding, yet little information exists to guide families regarding the safety of medicine use during lactation. Breastfeeding initiation or success may be altered by medicine use, and breastfeeding may obscure the true relationship between medicine exposure during pregnancy and developmental outcomes. Absent or poorly standardised recording of breastfeeding in most population databases hampers analysis and understanding of the complex relationships between medicine, pregnancy, breastfeeding and infant and maternal health. The purpose of this paper is to present the arguments for breastfeeding to be included alongside medicine use and neurodevelopmental outcomes in whole-population database investigations of the harms and benefits of medicines during pregnancy, the puerperium and postnatal period. We review: 1) the current situation, 2) how these complexities might be accommodated in pharmacoepidemiological models, using antidepressants and antiepileptics as examples; 3) the challenges in obtaining comprehensive data.

Conclusions

The scarcity of whole-population data and the complexities of the inter-relationships between breastfeeding, medicines, co-exposures and infant outcomes are significant barriers to full characterisation of the benefits and harms of medicines during pregnancy and breastfeeding. This makes it difficult to answer the questions: ‘is it safe to breastfeed whilst taking this medicine’, and ‘will this medicine interfere with breastfeeding and/ or infants’ development’?

Medications and Breast-Feeding: A Guide for Pharmacists, Pharmacy Technicians, and other Healthcare Professionals Part I

Objective:

To provide a guide for practicing pharmacists, pharmacy technicians, and other healthcare professionals so that they are able to counsel and advise breast-feeding mothers and fellow healthcare professionals on the safety and use of common ambulatory care, analgesic, and anesthetic medications during breast-feeding.

Data Sources:

Primary texts used by the breast-feeding community were searched, as well as Micromedex, MEDLINE, PubMed, Embase, and Embase2 (1984–July 2003).

Study Selection and Data Extraction:

Multiple sources were utilized whenever available to validate the data, and primary articles were used to verify all tertiary source information. Search terms included breast feeding, lactation, nursing, and medications, as well as specific drug names.

Data Synthesis:

Concerns regarding medication use during breast-feeding have caused mothers to either discontinue nursing or not take necessary medications. Complete avoidance of medications or cessation of breast-feeding is often unnecessary. Although there are medications that can be harmful to nursing infants, breast milk concentrations of most drugs are insufficient to cause any harm.

Conclusions:

Having objective and reliable information on medications enables pharmacists, pharmacy technicians, other healthcare providers, and mothers to make educated decisions regarding drug therapy and breast-feeding.

Therapeutic management of allergic diseases

Allergic diseases are characterized by the activation of inflammatory cells and by a massive release of mediators. The aim of this chapter was to describe succinctly the modes of action, indications, and side effects of the major antiallergic and antiasthmatic drugs. When considering the ideal pharmacokinetic characteristics of a drug, a poorly metabolized drug may confer a lower variability in plasma concentrations and metabolism-based drug interactions, although poorly metabolized drugs may be prone to transporter-based disposition and interactions. The ideal pharmacological properties of a drug include high binding affinity, high selectivity, and appropriate association and dissociation rates. Finally, from a patient perspective, the frequency and route of administration are important considerations for ease of use.

The identifying and counseling of breastfeeding women by pharmacists

OBJECTIVE

Concerns about medications influence breastfeeding decisions. Mothers may stop breastfeeding when they take medications. After the distribution of Thomas Hale's Medications and Mother's Milk (MMM) (Hale Publishing, Amarillo, TX, 2006) by the Rhode Island Department of Health (Providence, RI) in November 2006 to Rhode Island pharmacies, we investigated, during the summer of 2007, what strategies and resources pharmacists were using to identify breastfeeding women and guide medication recommendations.

METHODS

Copies of MMM were sent to 47 pharmacies in Rhode Island. Subsequently, one pharmacist at each site completed a confidential, 10-question written survey.

RESULTS

The survey response rate was 92%. More than half (58%) of the pharmacists surveyed never asked women if they were breastfeeding. Most (85%) of pharmacists reported feeling somewhat or very comfortable giving advice to breastfeeding women. All but one pharmacist who had received MMM reported using the reference at least monthly. More than half (52%) of the pharmacists reported using the Physician's Desk Reference (Thomson PDR, Montvale, NJ).

DISCUSSION

Pharmacists need a consistent approach to identify breastfeeding women and access to reliable, continuously updated resources to guide their advice about medication use to breastfeeding women. Physicians and pharmacists should collaborate to prevent medication use from being a barrier to breastfeeding.

Drugs that affect the fetus and newborn infant via the placenta or breast milk

In general, drugs that are taken by a mother during pregnancy or after birth may be transferred to the fetus or the infant (through breast milk). Many factors are involved that determine the amount of drugs that are transferred and their potential effects on the fetus or infant. A careful assessment of the risk versus benefit is necessary and should be individualized. In the breastfed infant, many measures can be undertaken further so that the amount of drug transferred to the infant is minimized.

Pseudoephedrine: effects on milk production in women and estimation of infant exposure via breastmilk

AIMS

To assess the effects of pseudoephedrine on breast blood flow, temperature and milk production, and to estimate the likely infant dose during breastfeeding.

METHODS

Eight lactating women (mean age 35 years and weight 69 kg) participated in a single-blind randomized crossover study of 60 mg pseudoephedrine hydrochloride vs placebo. Breast blood flow and surface temperature were measured from 0 to 4 h following the dose, and change in plasma prolactin was measured as the difference between predose and 1 h postdose concentrations. Milk production was measured for 24 h following placebo and pseudoephedrine. Infant dose of pseudoephedrine for a 60-mg dose administered four times daily to the mother was quantified as the product of average steady-state drug concentration in milk and an estimated milk production rate of 0.15 l x kg(-1) x day(-1) and expressed relative to the maternal weight-adjusted dose.

RESULTS

There were no physiologically significant changes in breast blood flow or temperature between the placebo and pseudoephedrine periods. The mean change in plasma prolactin was slightly (13.5%), but not significantly lower (t = 1.245, P = 0.253) after pseudoephedrine (1775 mU x l(-1)) compared with placebo (2014 mU x l(-1)). However, the mean milk volume was reduced by 24% from 784 ml x day(-1) in the placebo period to 623 ml x day(-1) in the pseudoephedrine period (difference between means 161 ml x day(-1) (95% CI: 63, 259 ml x day(-1)); t = 3.9, P = 0.006). Assuming maternal intake of 60 mg pseudoephedrine hydrochloride four times daily, the estimated infant dose of pseudoephedrine was 4.3% (95% CI, 3.2, 5.4%) of the weight-adjusted maternal dose.

CONCLUSIONS

A single dose of pseudoephedrine significantly reduced milk production. This effect was not attributable to changes in blood flow, but depression of prolactin secretion may be a contributing factor. At the maximum recommended pseudoephedrine doses, the calculated infant dose delivered via milk was < 10% of the maternal dose, and is unlikely to affect the infant adversely. The ability of pseudoephedrine to suppress lactation suggests a novel use for the drug.

Use of sertraline, paroxetine and fluvoxamine by nursing women

BACKGROUND

The pharmacological treatment of depression in nursing women requires information on the magnitude of medication exposure to the infant that may occur through breast milk.

AIMS

To examine serum concentrations of antidepressants in infants exposed to these medications through breast-feeding.

METHOD

Maternal and infant serum concentrations of sertraline, paroxetine and fluvoxamine were determined with high-performance liquid chromatography (limit of detection=1 ng/ml).

RESULTS

No detectable medication was present in any infant exposed to paroxetine (n=16) or fluvoxamine (n=4). Among infants exposed to sertraline (n=30), detectable medication was present in 24% of serum samples. A significant negative correlation was found between infant age and infant serum concentration. Sertraline was significantly more likely to be detected in an infant if the mother's daily dose was 100 mg or higher. No adverse sequelae occurred in any infant.

CONCLUSIONS

This study shows that paroxetine, fluvoxamine and sertraline produce minimal exposure to infants when taken by nursing mothers.