Duloxetine transfer across the placenta during pregnancy and into milk during lactation

A literature review of drug transport mechanisms during lactation

Despite the benefits of breastfeeding, lactating mothers who take prescribed medications may discontinue breastfeeding due to concerns associated with infant drug exposure in breastmilk. Consolidating the current knowledge of drug transport to breastmilk may inform understanding of the safety of medication use during lactation. This literature review summarizes the mechanisms of drug transport to breastmilk, details the physicochemical drug properties that may alter the extent of passive transport, and describes the expressional changes in mammary drug transporters that may affect active transport. During the period of 20 July 2023 to 11 August 2023, PubMed® was searched to identify journal articles pertinent to the mechanisms of drug transport from maternal plasma to breastmilk and the expression of mammary drug transporters during lactation. From the 28 studies included in this review, four mechanisms were identified for transporting drugs from maternal plasma to breastmilk: passive transport, active transport, lipid co-transport, and transcytosis. The lactational expression of 20 drug transporters was further summarized, with 9 transporters demonstrating downregulated expression during lactation and 11 transporters demonstrating upregulated expression during lactation. Understanding the mechanisms of drug transport to breastmilk may aid in estimating infant drug exposure, developing physiologically based pharmacokinetic (PBPK) models that describe drug transfer, and initiating clinical drug development programs in the lactating population.

Consensus Panel Recommendations for the Pharmacological Management of Breastfeeding Women with Postpartum Depression

INTRODUCTION

Our consensus statement aims to clarify the use of antidepressants and anxiolytics during breastfeeding amidst clinical uncertainty. Despite recent studies, potential harm to breastfed newborns from these medications remains a concern, leading to abrupt discontinuation of necessary treatments or exclusive formula feeding, depriving newborns of benefits from mother's milk.

METHODS

A panel of 16 experts, representing eight scientific societies with a keen interest in postpartum depression, was convened. Utilizing the Nominal Group Technique and following a comprehensive literature review, a consensus statement on the pharmacological treatment of breastfeeding women with depressive disorders was achieved.

RESULTS

Four key research areas were delineated: (1) The imperative to address depressive and anxiety disorders during lactation, pinpointing the risks linked to untreated maternal depression during this period. (2) The evaluation of the cumulative risk of unfavorable infant outcomes associated with exposure to antidepressants or anxiolytics. (3) The long-term impact on infants' cognitive development or behavior due to exposure to these medications during breastfeeding. (4) The assessment of pharmacological interventions for opioid abuse in lactating women diagnosed with depressive disorders.

CONCLUSIONS

The ensuing recommendations were as follows: Recommendation 1: Depressive and anxiety disorders, as well as their pharmacological treatment, are not contraindications for breastfeeding. Recommendation 2: The Panel advocates for the continuation of medication that has demonstrated efficacy during pregnancy. If initiating an antidepressant during breastfeeding is necessary, drugs with a superior safety profile and substantial epidemiological data, such as SSRIs, should be favored and prescribed at the lowest effective dose. Recommendation 3: For the short-term alleviation of anxiety symptoms and sleep disturbances, the Panel determined that benzodiazepines can be administered during breastfeeding. Recommendation 4: The Panel advises against discontinuing opioid abuse treatment during breastfeeding. Recommendation 5: The Panel endorses collaboration among specialists (e.g., psychiatrists, pediatricians, toxicologists), promoting multidisciplinary care whenever feasible. Coordination with the general practitioner is also recommended.

Pharmacokinetics of Antidepressants in Pregnancy

Depression is common in pregnant women. However, the rate of antidepressant treatment in pregnancy is significantly lower than in nonpregnant women. Although some antidepressants may cause potential risks to the fetus, not treating or withdrawing the treatment is associated with relapsing and adverse pregnancy outcomes such as preterm birth. Pregnancy-associated physiologic changes can alter pharmacokinetics (PK) and may impact dosing requirements during pregnancy. However, pregnant women are largely excluded from PK studies. Dose extrapolation from the nonpregnant population could lead to ineffective doses or increased risk of adverse events. To better understand PK changes during pregnancy and guide dosing decisions, we conducted a literature review to catalog PK studies of antidepressants in pregnancy, with a focus on maternal PK differences from the nonpregnant population and fetal exposure. We identified 40 studies on 15 drugs, with most data from patients taking selective serotonin reuptake inhibitors and venlafaxine. Most of the studies have relatively poor quality, with small sample sizes, reporting concentrations at delivery only, a large amount of missing data, and not including times and adequate dose information. Only four studies collected multiple samples following a dose and reported PK parameters. In general, there are limited data available regarding PK of antidepressants in pregnancy and deficiencies in data reporting. Future studies should provide accurate information on drug dosing and timing of dose, PK sample collection, and individual-level PK data.

Antidepressants and Antipsychotics in Human Pregnancy: Transfer Across the Placenta and Opportunities for Modeling Studies

There is limited information about the transfer of antidepressants and antipsychotics across the human placenta. The objective of the current review was to systematically screen the scientific literature using relevant keywords to collect quantitative data on placental transfer of these drugs in humans and to give an overview of current modeling approaches used in this context. The collected data encompassed clinically measured fetal:maternal (F:M) concentration ratios (ie, the ratio between drug concentrations measured in the umbilical cord and drug concentrations measured in the mother) and transfer data obtained from ex vivo cotyledon perfusion experiments. These data were found for 18 antidepressants and some of their pharmacologically active metabolites, and for 10 antipsychotics and the metabolites thereof. Based on the collected data, similar maternal and fetal exposure could be observed for only a few compounds (eg, norfluoxetine and desvenlafaxine), whereas for most drugs (eg, paroxetine, sertraline, and quetiapine), fetal exposure appeared to be on average lower than maternal exposure. Venlafaxine appeared to be an exception in that the data indicated equivalent or higher concentrations in the umbilical cord than in the mother. Physiologically based pharmacokinetic (PBPK) models were sporadically used to investigate maternal pharmacokinetics of antidepressants or antipsychotics (eg, for sertraline, aripiprazole, and olanzapine), although without explicitly addressing fetal drug exposure. It is recommended that PBPK modeling is applied more frequently to these drugs. Although no substitute for clinical studies, these tools can help to better understand pregnancy-induced pharmacokinetic changes and ultimately contribute to a more evidence-based pharmacotherapy of depression and psychosis in pregnant subjects.

Exposure to duloxetine during pregnancy and risk of congenital malformations and stillbirth: A nationwide cohort study in Denmark and Sweden

BACKGROUND

The prevalence of depression and the exposure to antidepressants are high among women of reproductive age and during pregnancy. Duloxetine is a selective serotonin-norepinephrine reuptake inhibitor (SNRI) approved in the United States and Europe in 2004 for the treatment of depression. Fetal safety of duloxetine is not well established. The present study evaluates the association of exposure to duloxetine during pregnancy and the risk of major and minor congenital malformations and the risk of stillbirths.

METHODS AND FINDINGS

A population-based observational study was conducted based on data from registers in Sweden and Denmark. All registered births and stillbirths in the medical birth registers between 2004 and 2016 were included. Malformation diagnoses were identified up to 1 year after birth. Logistic regression analyses were used. Potential confounding was addressed through multiple regression, propensity score (PS) matching, and sensitivity analyses. Confounder variables included sociodemographic information (income, education, age, year of birth, and country), comorbidity and comedication, previous psychiatric contacts, and birth-related information (smoking during pregnancy and previous spontaneous abortions and stillbirths). Duloxetine-exposed women were compared with 4 comparators: (1) duloxetine-nonexposed women; (2) selective serotonin reuptake inhibitor (SSRI)-exposed women; (3) venlafaxine-exposed women; and (4) women exposed to duloxetine prior to, but not during, pregnancy. Exposure was defined as redemption of a prescription during the first trimester and throughout pregnancy for the analyses of malformations and stillbirths, respectively. Outcomes were major and minor malformations and stillbirths gathered from the national patient registers. The cohorts consisted of more than 2 million births with 1,512 duloxetine-exposed pregnancies. No increased risk for major malformations, minor malformations, or stillbirth was found across comparison groups in adjusted and PS-matched analyses. Duloxetine-exposed versus duloxetine-nonexposed PS-matched analyses showed odds ratio (OR) 0.98 (95% confidence interval [CI] 0.74 to 1.30, p = 0.909) for major malformations, OR 1.09 (95% CI 0.82 to 1.45, p = 0.570) for minor malformation, and 1.18 (95% CI 0.43 to 3.19, p = 0.749) for stillbirths. For the individual malformation subtypes, some findings were statistically significant but were associated with large statistical uncertainty due to the extremely small number of events. The main limitations for the study were that the indication for duloxetine and a direct measurement of depression severity were not available to include as covariates.

CONCLUSIONS

Based on this observational register-based nationwide study with data from Sweden and Denmark, no increased risk of major or minor congenital malformations or stillbirth was associated with exposure to duloxetine during pregnancy.

Antidepressant transfer into amniotic fluid, umbilical cord blood & breast milk: A systematic review & combined analysis

OBJECTIVE

Data regarding the ability of antidepressants to enter fetal, newborn and infant fluids have become gradually available, but mechanisms of antidepressant transfer remain poorly understood. Here we calculated penetration ratios in an array of matrices from combined samples of pregnant/breastfeeding women taking antidepressants.

METHOD

We performed a systematic literature search of PubMed and EMBASE to identify studies with concentrations of antidepressants from maternal blood, amniotic fluid, umbilical cord blood and/or breast milk. Penetration ratios were calculated by dividing the concentrations in amniotic fluid, umbilical cord plasma or breast milk by the maternal plasma concentration. When data from multiple studies were available, we calculated combined penetration ratios, weighting the study mean by study size.

RESULTS

Eighty-five eligible studies were identified. For amniotic fluid, the highest penetration ratios were estimated for venlafaxine (mean 2.77, range 0.43-4.70 for the active moiety) and citalopram (mean 2.03, range 0.35-6.97), while the lowest ratios were for fluvoxamine (mean 0.10) and fluoxetine (mean 0.11, range 0.02-0.20 for the active moiety). For umbilical cord plasma, nortriptyline had the highest ratio (mean 2.97, range 0.25-26.43) followed by bupropion (mean 1.14, range 0.3-5.08). For breast milk, the highest ratios were observed for venlafaxine (mean 2.59, range 0.85-4.85), mianserin (mean 2.22, range 0.80-3.64) and escitalopram (mean 2.19, range 1.68-3.00).

CONCLUSION

We observed considerable variability across antidepressants regarding their ability to enter fetal, newborn and infant fluids. Measuring antidepressant concentrations in a maternal blood sample can provide a reliable estimate of fetal/infant exposure, although further evidence for concentration-dependent effects is required.

A New Safety Scoring System for the Use of Psychotropic Drugs During Lactation

BACKGROUND

Psychotropic drugs are frequently used to treat postpartum women with psychiatric diagnoses, especially psychotic disorder, major depression, and bipolar mood episodes. Pharmacotherapy in breastfeeding mothers is a major challenge.

STUDY QUESTION

This article presents a new safety scoring system for the use of psychotropic drugs during lactation.

STUDY DESIGN

The scoring system is based on the following 6 safety parameters: reported total sample, reported maximum relative infant dose, reported sample size for relative infant dose, infant plasma drug levels, prevalence of reported any adverse effect, and reported serious adverse effects. The total score ranges from 0 to 10. Higher scores represent a higher safety profile.

RESULTS

According to this scoring system, sertraline and paroxetine, respectively, had the highest scores representing "very good safety profile." Citalopram, olanzapine, and midazolam were assigned to "good safety profile." Among drugs evaluated in this article, trifluoperazine, aripiprazole, amisulpride, clozapine, doxepin, zaleplon, and zolpidem are not recommended owing to safety scores ≤3.

CONCLUSIONS

Most psychotropic drugs examined in this article have "moderate" or "low" safety profile.

Prediction of human fetal-maternal blood concentration ratio of chemicals

Background

The measurement of human fetal-maternal blood concentration ratio (logFM) of chemicals is critical for the risk assessment of chemical-induced developmental toxicity. While a few in vitro and ex vivo experimental methods were developed for predicting logFM of chemicals, the obtained experimental results are not able to directly predict in vivo outcomes.

Methods

A total of 55 chemicals with logFM values representing in vivo fetal-maternal blood ratio were divided into training and test datasets. An interpretable linear regression model was developed along with feature selection methods. Cross-validation on training dataset and prediction on independent test dataset were conducted to validate the prediction model.

Results

This study presents the first valid quantitative structure-activity relationship model following the Organisation for Economic Co-operation and Development (OECD) guidelines based on multiple linear regression for predicting in vivo logFM values. The autocorrelation descriptor AATSC1c and information content descriptor ZMIC1 were identified as informative features for predicting logFM. After the adjustment of the applicability domain, the developed model performs well with correlation coefficients of 0.875, 0.850 and 0.847 for model fitting, leave-one-out cross-validation and independent test, respectively. The model is expected to be useful for assessing human transplacental exposure.

Managing fibromyalgia syndrome in pregnancy no bridges between USA and EU

The first aim of this article is to analyze the risk/benefit ratio of using psychotropic drugs approved in some countries for treating fibromyalgia syndrome (FMS) during pregnancy. Assessing the effectiveness of non-pharmacological interventions is the second scope of this article, in order to help clinicians to manage FMS in pregnancy in those countries were no drugs are approved for treating the disease. Following the PRISMA guidelines for systematic reviews, a literature search was conducted on PubMed and Google Scholar. Separate literature searches were performed for the three psychotropic drugs approved in the USA for treating FMS, psychotherapy, and transcranial magnetic stimulation (TMS). Perinatal duloxetine exposure is associated with increased risk of gestational and perinatal complications. With regards pregabalin, available information suggests that the drug is not devoid of structural teratogenicity potential. No data are available for milnacipran. Duloxetine and pregabalin should be only given to pregnant women diagnosed with severe forms of FMS after carefully weighing the benefits and risks for the mother-fetus dyad. On the other hand, we have to consider that the proportion of women who discontinue psychotropic drugs during pregnancy is as high as 85.4%. This figure raises further questions about adequate alternative treatment of FMS during the perinatal period. Moreover, neither duloxetine nor milnacipran or pregabalin have been approved by the EMEA for the treatment of FMS. Unfortunately, psychological treatment of FMS in perinatal women are not yet tested and data on TMS are conflicting.

Cluster analysis profiling of behaviors in zebrafish larvae treated with antidepressants and pesticides

Antidepressants are used by a substantial number of women in their childbearing years. Treatment may continue during pregnancy, since untreated depression poses a risk to the mother and child. However, many antidepressants readily pass through the placental barrier to reach the fetus or may be ingested by the newborn via breastmilk. Little is known about the effects of antidepressants on brain development and subsequent behavior in young children. In the current study, we used zebrafish as a model system to examine the neurodevelopmental effects of three commonly prescribed antidepressants, sertraline, duloxetine and bupropion. Zebrafish were exposed to these antidepressants during development and were examined for changes in larval avoidance behavior, activity, social behaviors, and anxiety-related behaviors. The results show that antidepressants commonly affect larval swim speeds and resting, and differentially affect other behaviors depending upon the exposure period. Using cluster analysis profiling, we compared the obtained results to previous reports on behavioral defects induced by organophosphate pesticides. We found that the behavioral profiles induced by antidepressants and pesticides overlap, indicating a common mechanism of action. We conclude that developmental antidepressant exposures lead to specific behavioral changes in zebrafish larvae. At present, it is not known if antidepressants have similar effects in human development.

Infant Exposure to Methylphenidate and Duloxetine During Lactation

BACKGROUND

Duloxetine and methylphenidate are commonly prescribed for the management of depression and attention-deficit/hyperactivity disorder (ADHD), respectively. However, little information is available concerning their safety during lactation. The purpose of this case series was to provide additional information to the medical literature concerning infant exposure to methylphenidate and duloxetine through breast milk.

METHOD

Bioanalytical method (liquid chromatography coupled to mass spectrometry) was developed and validated before its use to determine the concentrations of both medications in breast milk samples.

CASES

Case 1: A 30-year-old woman with depression and ADHD took duloxetine 90 mg daily and methylphenidate 36 mg daily during pregnancy and breastfeeding. The newborn was found to have a congenital pulmonary airway malformation. The breastfeeding status was nonexclusive. At week 4 postpartum, the concentration found in the milk was 32.8 ng/mL of duloxetine and 7.9 ng/mL of methylphenidate (estimated relative infant dose [RID] of 0.3% and 0.2%, respectively). Case 2: A 41-year-old women with depression took duloxetine 60 mg daily during pregnancy and lactation. She gave birth to a healthy child. The breastfeeding status was nonexclusive. Cord to maternal plasma concentration ratio was 0.4. At day 6 postpartum, the concentration of duloxetine was 23.6 ng/mL in the foremilk and 14.3 ng/mL in the hindmilk (RID of 0.4% and 0.2%, respectively). At week 6 postpartum, the concentration was 25.2 ng/mL in the foremilk and 29.3 ng/mL in the hindmilk (RID of 0.4% and 0.4%, respectively).

CONCLUSION

In accordance with previously published data, this case series suggests a minimal exposure to duloxetine and methylphenidate through breast milk. Thus, these drugs are likely compatible with lactation. However, large cohort studies are necessary to evaluate their long-term impact on the exposed infants.

Use of Psychotropic Medications in Breastfeeding Women

BACKGROUND

Breastfeeding women who are prescribed with psychotropic medications on a regular basis are often concerned, regarding the possible implications of such treatment on the breastfed infant. A mother's well-being has a direct influence on the well-being of the baby. However, the notorious reputation of psychotropic medications may lead to suboptimal prescribing by the physician and poor adherence by the mother.

METHODS

A PubMed search (from 1976 through February 2017) was conducted for commonly used psychotropic drug classes, as well as individual medications commonly prescribed in these classes, along with the MeSH terms "breastfeeding"/"lactation". In each case, we chose studies that describe the pharmacokinetics of passage into breast milk and/or adverse effects in breastfed infants.

RESULTS

No large-scale controlled studies regarding the safety of psychotropic medications in breastfeeding mothers were reported. Based on case reports and small studies, most psychotropic medications produce low milk levels and low plasma levels in the infant, while serious adverse effects in the breastfed infant are rarely reported. Safety data for some psychotropic medications are still unavailable.

CONCLUSION

According to the data available in the literature to date, most psychotropic medications are expected to produce low levels in breast milk with no clinical importance. Nevertheless, an individual risk-benefit assessment of a proposed treatment should always be performed, as inter-individual differences may have a substantial effect on the breastfeeding infant's response to the treatment. Further studies and additional objective data are needed to consolidate and improve our current knowledge of psychopharmacotherapy in breastfeeding women. Birth Defects Research 109:957-997, 2017. © 2017 Wiley Periodicals, Inc.

Quantitative structure-activity relationship model for the fetal-maternal blood concentration ratio of chemicals in humans

A quantitative structure-activity relationship (QSAR) model of the fetal-maternal blood concentration ratio (F/M ratio) of chemicals was developed to predict the placental transfer in humans. Data on F/M ratio of 55 compounds found in the literature were separated into training (75%, 41 compounds) and testing sets (25%, 14 compounds). The training sets were then subjected to multiple linear regression analysis using the descriptors of molecular weight (MW), topological polar surface area (TopoPSA), and maximum E-state of hydrogen atom (Hmax). Multiple linear regression analysis and a cross-validation showed a relatively high adjusted coefficient of determination (Ra(2)) (0.73) and cross-validated coefficient of determination (Q(2)) (0.71), after removing three outliers. In the external validation, R(2) for external validation (R(2)pred) was calculated to be 0.51. These results suggested that the QSAR model developed in this study can be considered reliable in terms of its robustness and predictive performance. Since it is difficult to examine the F/M ratio in humans experimentally, this QSAR model for prediction of the placental transfer of chemicals in humans could be useful in risk assessment of chemicals in humans.

Placental transfer of antidepressant medications: implications for postnatal adaptation syndrome

Seven to thirteen percent of women are either prescribed or taking (depending on the study) an antidepressant during pregnancy. Because antidepressants freely cross into the intrauterine environment, we aim to summarize the current findings on placental transfer of antidepressants. Although generally low risk, antidepressants have been associated with postnatal adaptation syndrome (PNAS). Specifically, we explore whether the antidepressants most closely associated with PNAS (paroxetine, fluoxetine, venlafaxine) cross the placenta to a greater extent than other antidepressants. We review research on antidepressants in the context of placental anatomy, placental transport mechanisms, placental metabolism, pharmacokinetics, as well as non-placental maternal and fetal factors. This provides insight into the complexity involved in understanding how placental transfer of antidepressants may relate to adverse perinatal outcomes. Ultimately, from this data there is no pattern in which PNAS is related to placental transfer of antidepressant medications. In general, there is large interindividual variability for each type of antidepressant. To make the most clinically informed decisions about the use of antidepressants in pregnancy, studies that link maternal, placental and fetal genetic polymorphisms, placental transfer rates and infant outcomes are needed.

ABM Clinical Protocol #18: Use of Antidepressants in Breastfeeding Mothers

A central goal of The Academy of Breastfeeding Medicine is the development of clinical protocols for managing common medical problems that may impact breastfeeding success. These protocols serve only as guidelines for the care of breastfeeding mothers and infants and do not delineate an exclusive course of treatment or serve as standards of medical care. Variations in treatment may be appropriate according to the needs of an individual patient.

The safety of serotonin-noradrenaline reuptake inhibitors (SNRIs) in pregnancy and breastfeeding: a comprehensive review

OBJECTIVE

The present study provides a comprehensive review of the existing literature on the safety of serotonin-noradrenaline reuptake inhibitors (SNRIs) in pregnancy and lactation.

METHODS

Studies published in English, reporting the use of SNRIs in pregnant and/or breastfeeding women, were identified by searching MEDLINE/Pubmed, PsycINFO, and EMBASE.

RESULTS

Twenty-nine studies were included in the review. Altogether, the initial evidence coming from the reviewed studies suggests a lack of association between SNRIs and an increased risk of major congenital malformations. Conversely, exposure to SNRIs seems to be significantly associated with an increased risk of some perinatal complications. No neonatal adverse events emerged, so far, in the few studies concerning the safety of SNRIs during breastfeeding.

CONCLUSIONS

Available data suggest that venlafaxine is relatively safe during pregnancy, in particular as far as major malformations are concerned, whereas considering the small number of studies published, no definitive conclusions can be drawn on its safety during breastfeeding. Because of the few studies so far published, the safety of duloxetine during pregnancy and breastfeeding remains to be well established.

Serotonin reuptake inhibitors and breastfeeding: a systematic review

OBJECTIVE

The postnatal period represents a critical phase for mothers because of physiological hormonal changes, the increase of emotional reactions and a greater susceptibility for the onset/recrudescence of psychiatric disorders. Despite the evidence of an increasing utilization of antidepressant drugs during breastfeeding, there is still few reliable information on the neonatal safety of the selective serotonin reuptake inhibitors (SSRIs) and selective noradrenergic reuptake inhibitors (SNRIs) [serotonin reuptake inhibitors (SRIs)] in nursing mothers. The aim of this study is to provide a systematic review on the neonatal safety profile of these drugs during breastfeeding, also assessing the limits of available tools.

METHODS

MEDLINE and PubMed databases were searched without any language restrictions by using the following set of keywords: ((SSRIs OR selective serotonin inhibitor reuptake OR SNRIs OR selective serotonin noradrenaline inhibitor reuptake) AND (breastfeeding OR lactation OR breast milk)). A separate search was also performed for each SSRIs (paroxetine, fluvoxamine, fluoxetine, sertraline, citalopram and escitalopram) and SNRIs (venlafaxine and duloxetine).

RESULTS

Sertraline and paroxetine show a better neonatal safety profile during breastfeeding as compared with other SRIs. Less data are available for fluvoxamine, escitalopram and duloxetine. Few studies followed up infants breastfeed for assessing the neurodevelopmental outcomes.

CONCLUSIONS

Literature review clearly indicates paroxetine and sertraline as the drugs that should be preferred as first line choice in nursing women who need an antidepressant treatment.