A guide to the safety of CNS-active agents during breastfeeding

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

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 antiinfectives, vaccines, antiepileptics, benzodiazepines, psychotherapeutic drugs, and radiopharmaceuticals during breast-feeding.

Data Sources:

Primary texts used by the breast-feeding community ( Medications and Mothers' Milk, Drugs in Pregnancy and Lactation, Drugs and Human Lactation) were searched, as well as Micromedex, MEDLINE, PubMed, EMBASE, and EMBASE2 (1984–February 2004).

Study Selection/Data Extraction:

Multiple sources were used wherever 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 drugs 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.

SSRIs during breastfeeding: spotlight on milk-to-plasma ratio

OBJECTIVE

To investigate the usefulness of the milk-to-plasma (M/P) ratio for assessing the risks for the breastfed infant associated with the maternal use of SSRIs.

DATA SOURCES

Medline, Toxnet, Embase, Current Contents, and PsycInfo indexed articles from 1980 to September 2006.

STUDY SELECTION AND DATA EXTRACTION

All studies reporting the M/P ratio in mothers taking SSRIs while breastfeeding or studies which such an information could be calculated from data reported in the article.

DATA SYNTHESIS

Higher M/P ratios were rarely associated with a clinically significant impact on the babies during the early phases of breastfeeding.

CONCLUSIONS

So far no evidence-based information seems to support the hypothesis that SSRIs characterized by a M/P ratio <1.0 should be preferred. Hence, physicians should consider different parameters when attempting to choose the safest SSRI for the breastfeeding woman. These parameters might be represented by the number of well-documented published adverse event reports and the tendency of each SSRI of inducing in the infants serum concentrations that are elevated above 10% of average maternal serum levels. In any case, if the mother wishes to breastfeed her infant while taking a SSRI, the baby should be closely monitored in order to promptly detect any iatrogenic event.

SSRIs in pregnancy and lactation: emphasis on neurodevelopmental outcome

The aim of this review was to assess existing information about the long-term neurocognitive development of children whose mothers took SSRIs during pregnancy and/or breastfeeding. The available literature consists of 11 studies (examining a total of 306 children) that demonstrate no impairment of infant neurodevelopment following prenatal and/or postnatal exposure to SSRIs, and two studies (examining 81 children) that suggest possible unwanted effects of fetal SSRI exposure. These unwanted effects included subtle effects on motor development and motor control. Thus, the available data are not unanimous in excluding possible long-term detrimental neurodevelopmental sequelae of intrauterine exposure to SSRIs. However, it is clear that the research suggesting a lack of adverse events on infants' neurocognitive development is much more numerous and methodologically better conducted than the studies showing possible unwanted effects. Nevertheless, all reviewed studies had procedural inadequacies, and the screening instruments used have limitations, especially in the evaluation of infants. Furthermore, it is not advisable to extend the generalisations emerging from the findings of a few trials to every infant. Some infants may experience difficulties in metabolising the drugs and/or their metabolites, so the benign outcome described for most infants may not occur. Thus, the findings emerging from the reports are inconclusive and are not able to fully clarify the repercussions of maternal SSRI treatment on infants' long-term neurocognitive development. Further large, simple and well designed, randomised, prospective studies will be required for this purpose. These should also be of adequate length and performed using reproducible neurophysiological parameters in order to firmly establish the safety of these medications.

Australian and New Zealand clinical practice guidelines for the treatment of bipolar disorder

BACKGROUND

The Royal Australian and New Zealand College of Psychiatrists is co-ordinating the development of clinical practice guidelines (CPGs) in psychiatry, funded under the National Mental Health Strategy (Australia) and the New Zealand Health Funding Authority

METHOD

For these guidelines, the CPG team reviewed the treatment outcome literature (including meta-analyses) and consulted with practitioners and consumers.

TREATMENT RECOMMENDATIONS

This guideline provides evidence-based recommendations for the management of bipolar disorder by phase of illness, that is acute mania, mixed episodes and bipolar depression, and the prophylaxis of such episodes. It specifies the roles of various mood-stabilizing medications and of psychological treatments such as cognitive therapy and psycho-education.

Pharmacokinetic study of carbamazepine and its carbamazepine 10,11-epoxide metabolite in a group of female epileptic patients under chronic treatment

BACKGROUND

Although epileptic crises are equally frequent in women and men, several factors cause female epileptics to present a series of gender-specific problems. To date, few studies have been published on the kinetics of carbamazepine (CBZ) and carbamazepine 10,11-epoxide (CBZ-E) active metabolite in a Mexican population, and no information for epileptic women of reproductive age is available. The aim of the present work was to study the pharmacokinetic behavior of this group of women during steady state.

METHODS

Fourteen epileptic women under chronic treatment receiving only the anticonvulsant CBZ to control their crises were studied. A blood sample was taken before breakfast, before the morning dose of 200 mg, and after the dose at 1, 2, 3, 4, 5, and 8 h. Serum was separated by centrifugation at 1,350 x g. Serum concentrations of carbamazepine (CBZ) and of the metabolite carbamazepine 10,11-epoxide (CBZ-E) were measured by HPLC. Pharmacokinetic parameters were calculated by statistical moment method after obtaining serum concentrations.

RESULTS

Maximum time (T(max)) for CBZ was reached at 2.72+/-0.71 h and for CBZ-E, it was 3.60+/-0.79 h. C(max) for CBZ was 7.30+/-2.30 microg/mL, while C(min) for CBZ was 6.30+/-2.49. Maximum serum values for CBZ-E were 1.01+/-0.57, equivalent to 13.80% of CBZ; t(12) value for CBZ and CBZ-E was 18.20 and 16.10 h, respectively. AUC values for CBZ and metabolite were 70.33+/-17.10 microg/L/h and 9.20+/-2.50 microg/L/h, respectively. CBZ and CBZ-E clearance did not show differences and were 0.37 mL/kg/min and 0.40 mL/kg/min, respectively. Extraction index for serum concentrations of CBZ and CBZ-E AUC(CBZ)/AUC(CBZ-E) was 0.13; positive correlation was observed between serum concentrations of CBZ and E-CBZ, with r=0.94.

CONCLUSIONS

The schedule we suggest for therapeutic monitoring of serum concentrations of CBZ in chronic treatments is 3 h for maximum peak concentration of C(max) after dose administration and for minimum peak concentration, C(min) prior to subsequent administration of the dose.

Structural effects and neurofunctional sequelae of developmental exposure to psychotherapeutic drugs: experimental and clinical aspects

The advent of psychotherapeutic drugs has enabled management of mental illness and other neurological problems such as epilepsy in the general population, without requiring hospitalization. The success of these drugs in controlling symptoms has led to their widespread use in the vulnerable population of pregnant women as well, where the potential embryotoxicity of the drugs has to be weighed against the potential problems of the maternal neurological state. This review focuses on the developmental toxicity and neurotoxicity of five broad categories of widely available psychotherapeutic drugs: the neuroleptics, the antiepileptics, the antidepressants, the anxiolytics and mood stabilizers, and a newly emerging class of nonprescription drugs, the herbal remedies. A brief review of nervous system development during gestation and following parturition in mammals is provided, with a description of the development of neurochemical pathways that may be involved in the action of the psychotherapeutic agents. A thorough discussion of animal research and human clinical studies is used to determine the risk associated with the use of each drug category. The potential risks to the fetus, as demonstrated in well described neurotoxicity studies in animals, are contrasted with the often negative findings in the still limited human studies. The potential risk fo the human fetus in the continued use of these chemicals without more adequate research is also addressed. The direction of future research using psychotherapeutic drugs should more closely parallel the methodology developed in the animal laboratories, especially since these models have already been used extremely successfully in specific instances in the investigation of neurotoxic agents.

Antipsychotics and breastfeeding

Nearly 10% of all postpartum women will experience some form of psychiatric illness. The development of postpartum psychosis consisting of symptoms such as auditory hallucinations, delusions, and disorganization is greatest within the first 4 weeks after delivery. In fact, a majority of cases (54%) occur within 14 days of delivery. Due to a more favorable side-effect profile, atypical antipsychotics are generally preferred over traditional antipsychotics for the treatment of psychotic symptoms. Unfortunately, there are minimal guidelines established with regard to the use of antipsychotics during lactation. This article will review currently available data on the excretion of traditional and atypical antipsychotics into breast milk and make recommendations with regard to the use of individual agents during lactation.

Antidepressants and breast-feeding: a review of the literature

For every antidepressant so far investigated in the breast milk of mothers prescribed these medications, findings indicate that some amount of drug will be excreted into the breast milk. Nursing infants will be exposed to some, usually a very low, amount of drug and drug metabolites. Levels of drug exposure to infants for the many antidepressants available are examined, discussing milk to plasma drug concentration ratios and the infant dose as a percentage of the maternal dose. Drug concentrations in infant plasma and adverse effects of drug exposures to infants are reviewed. Factors influencing the decision on whether to breast or bottle feed an infant nursed by a mother taking antidepressants are discussed, concluding that the decision needs to be made on an individual basis. The lactating mother, in consultation with her doctor, should be in a position to make an informed decision on whether or not to breast feed. Under certain circumstances the decision to bottle feed may be wise, but more commonly the advantages of breast-feeding will outweigh the very low risk of an adverse event from drug exposure to the infant.

Anticonvulsants and breast feeding: a critical review

Progress in the diagnosis and management of seizure disorders and the availability of effective anticonvulsive medications has enabled increasing numbers of epileptic women of child-bearing age to raise families. Breast feeding, which these women may wish to choose, provides health, nutritional, immunological, developmental, social, economic and environmental benefits. The traditional anticonvulsants, such as phenytoin, carbamazepine and valproic acid (valproate sodium), are generally considered safe for use during breast feeding; however, observation for adverse effects is recommended. The use of phenobarbital while breast feeding is controversial because of its slow elimination by the nursing infant. The newer anticonvulsants, such as clobazam, felbamate, gabapentin, lamotrigine, oxcarbazepine, tiagabine, topiramate, and vigabatrin, are used mainly as adjunctive therapy. Data on the use of these drugs in pregnancy and lactation, and regarding long term effects on cognition and behaviour, are sparse. Weighing the benefits of breast feeding against the potential risk to the nursing infant, breast feeding is considered to be safe when the mother is taking carbamazepine, valproic acid or phenytoin. Infant monitoring for potential adverse effects is advisable when the mother is taking phenobarbital, clobazam, gabapentin, lamotrigine, oxcarbazepine or vigabatrin. Monitoring of infant serum drug concentrations is advisable but not compulsory. The use of felbamate, tiagabine and topiramate during breast feeding should await further study.

Use of psychotropic medications in breast-feeding women: acute and prophylactic treatment

OBJECTIVES

The postnatal period is a time of increased onset and relapse of mental illness. It poses a clinical dilemma, as many mothers requiring medication acutely or prophylactically will also choose to breast feed. The present paper first reviews the safety of psychotropes in breast-fed infants and the usefulness of prophylaxis for women at risk of postpartum affective relapse and, second, provides guidelines in the use of psychotropic drugs in breast-feeding women.

METHODS

A Medline review was conducted reviewing all papers published during the period 1993-1998 (and their associated bibliographies) on the use of psychotropes in breast-feeding women and the prophylactic usefulness of medications in women at risk of affective postpartum relapse.

RESULTS

Findings are based on case reports and small, mostly uncontrolled studies. Both tricyclic antidepressants (TCA) and specific serotonin re-uptake inhibitors (SSRIs) appear to be relatively safe in breast feeding. Antidepressants commenced in the early postpartum period may reduce depressive relapse. While prophylactic lithium appears to significantly reduce relapse of affective psychosis in the puerperium, there have been no studies of the anticonvulsants in the puerperium. Finally, high dose antipsychotics should be avoided, as they may be associated with long-term adverse sequelae in the infant.

CONCLUSIONS

On the basis of current knowledge, the use of SSRIs, TCA, carbamazepine, sodium valproate and short-acting benzodiazepines in breast feeding is relatively safe. If lithium is to be used, close collaboration with a paediatrician is essential. The long-term risks of antipsychotics, especially at high doses, remain to be clarified. Before a decision can be made, the risk-benefit ratio must be clearly outlined and discussed with the mother and her partner.