A clinical tool for reducing central nervous system depression among neonates exposed to codeine through breast milk

Dutch Pharmacogenetics Working Group (DPWG) guideline for the gene-drug interaction between CYP2D6 and opioids (codeine, tramadol and oxycodone)

The current Dutch Pharmacogenetics Working Group (DPWG) guideline, describes the gene-drug interaction between CYP2D6 and the opioids codeine, tramadol and oxycodone. CYP2D6 genotype is translated into normal metaboliser (NM), intermediate metaboliser (IM), poor metaboliser (PM) or ultra-rapid metaboliser (UM). Codeine is contraindicated in UM adults if doses >20 mg every 6 h (q6h), in children ≥12 years if doses >10 mg q6h, or with additional risk factors. In PMs, an alternative analgesic should be given which is not or to a lesser extent metabolised by CYP2D6 (not tramadol). In IMs with insufficient analgesia, a higher dose or alternative analgesic should be given. For tramadol, the recommendations for IMs and PMs are the same as the recommendation for codeine and IMs. UMs should receive an alternative drug not or to a lesser extent metabolised by CYP2D6 or the dose should be decreased to 40% of the commonly prescribed dose. Due to the absence of effect on clinical outcomes of oxycodone in PMs, IMs and UMs no action is required. DPWG classifies CYP2D6 genotyping for codeine "beneficial" and recommends testing prior to, or shortly after initiation of treatment in case of higher doses or additional risk factors. CYP2D6 genotyping is classified as "potentially beneficial" for tramadol and can be considered on an individual patient basis.

Pharmacogenomics in Children

Historically genetics has not been considered when prescribing drugs for children. However, it is clear that genetics are not only an important determinant of disease in children but also of drug response for many important drugs that are core agents used in the therapy of common problems in children. Advances in therapy and in the ethical construct of children's research have made pharmacogenomic assessment for children much easier to pursue. It is likely that pharmacogenomics will become part of the therapeutic decision-making process for children, notably in areas such as childhood cancer where weighing benefits and risks of therapy is crucial.

Prevalence and duration of prescribed opioid use during pregnancy: a cohort study from the Quebec Pregnancy Cohort

Background

Recent studies show a rapid growth among pregnant women using high potency opioids for common pain management during their pregnancy. No study has examined the duration of treatment among strong opioid users and weak opioid users during pregnancy. We aimed to investigate the prevalence of prescribed opioid use during pregnancy, in Quebec; and to compare the duration of opioid treatment between strong opioid users and weak opioid users.

Methods

Using the Quebec Pregnancy Cohort (1998–2015), we included all pregnancies covered by the Quebec Public Prescription Drug Insurance Program. Opioid exposure was defined as filled at least one prescription for any opioid during pregnancy or before pregnancy but with a duration that overlapped the beginning of pregnancy. Prevalence of opioids use was calculated for all pregnancies, according to pregnancy outcome, trimester of exposure, and individual opioids. The duration of opioid use during pregnancy was analyzed according to 8 categories based on cumulative duration (< 90 days vs. ≥90 days), duration of action (short-acting vs. long-acting) and strength of the opioid (weak vs. strong).

Results

Of 442,079 eligible pregnancies, 20,921 (4.7%) were exposed to opioids. Among pregnancies ending with deliveries (n = 249,234), 5.4% were exposed to opioids; the prevalence increased by 40.3% from 3.9% in 1998 to 5.5% in 2015, more specifically a significant increase in the second and third trimesters of pregnancy. Weak opioid, codeine was the most commonly dispensed opioid (70% of all dispensed opioids), followed by strong opioid, hydromorphone (11%), morphine (10%), and oxycodone (5%). The prevalence of codeine use decreased by 47% from 4.3% in 2005 to 2.3% in 2015, accompanied by an increased use of strong opioid, morphine (0.029 to 1.41%), hydromorphone (0.115 to 1.08%) and oxycodone (0.022 to 0.44%), from 1998 to 2015. The average durations of opioid exposure were significantly longer among pregnancies exposed to strong opioid as compared to weak opioid regardless of the cumulative duration or duration of action (P < 0.05).

Conclusions

Given the differences in the safety profile between strong opioids and the major weak opioid codeine, the increased use of strong opioids during pregnancy with longer treatment duration raises public health concerns.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04270-x.

Pharmacologic Stepwise Multimodal Approach for Postpartum Pain Management: ACOG Clinical Consensus No. 1

SUMMARY

Pain in the postpartum period is common and considered by many individuals to be both problematic and persistent (1). Pain can interfere with individuals' ability to care for themselves and their infants, and untreated pain is associated with risk of greater opioid use, postpartum depression, and development of persistent pain (2). Clinicians should therefore be skilled in individualized management of postpartum pain. Though no formal time-based definition of postpartum pain exists, the recommendations presented here provide a framework for management of acute perineal, uterine, and incisional pain. This Clinical Consensus document was developed using an a priori protocol in conjunction with the authors listed. This document has been revised to incorporate more recent evidence regarding postpartum pain.

The Effectiveness and Safety of Intravenous Dexmedetomidine of Different Concentrations Combined with Butorphanol for Post-Caesarean Section Analgesia: A Randomized Controlled Trial

Purpose

The present study aimed to determine the effectiveness of intravenous dexmedetomidine of different concentrations and to evaluate its maternal and neonatal safety when combined with butorphanol in parturients undergoing cesarean section.

Patients and Methods

A total of 114 parturients between 24 and 43 years of age, with singleton pregnancy who underwent elective cesarean section under epidural anesthesia, were randomly allocated to four groups: group C received 0.9% sodium chloride after delivery, followed by butorphanol (3 μg·kg^-1·h^-1); patients in groups D1, D2, and D3 received 0.5 μg·kg^-1·h^-1 dexmedetomidine after delivery, followed by butorphanol (3 μg·kg^-1·h^-1) combined with dexmedetomidine 0.03, 0.05, and 0.08 μg·kg^-1·h^-1, respectively. The primary outcome was the visual analogue scale (VAS) score at 6 h after delivery when patients were at rest. Secondary outcome measures included VAS after delivery when patients were on movement and uterine cramping, Ramsay sedation scale (RSS), relative infant dose (RID) of dexmedetomidine, satisfaction with analgesia after surgery and symptoms of CNS depression in neonates.

Results

There were no significant differences in patient characteristics among the groups (P > 0.05). The VAS at all timepoints after delivery in groups D2 and D3 were significantly lower than in groups C and D1 (P < 0.001). RSS scores were clearly higher in group D3 than in the other three groups at 6 h and 12 h (P < 0.0001). RID in groups D1, D2, and D3 was 0.171%, 0.197%, and 0.370%, respectively. Compared with group D1, RID was higher in group D3 (P = 0.0079). Degree of satisfaction with analgesia was higher in groups D2 and D3 (P < 0.005).

Conclusion

Continuous intravenous infusion of 0.05 μg·kg^-1·h^-1 dexmedetomidine combined with 3 μg·kg^-1·h^-1 butorphanol could be safely applied in healthy parturients with satisfactory analgesia after cesarean section without changes in sedation.

ABCB1, ABCG2, ABCC1, ABCC2, and ABCC3 drug transporter polymorphisms and their impact on drug bioavailability: what is our current understanding?

INTRODUCTION

Interindividual differences in drug response are a frequent clinical challenge partly due to variation in pharmacokinetics. ATP-binding cassette (ABC) transporters are crucial determinants of drug disposition. They are subject of gene regulation and drug-interaction; however, it is still under debate to which extend genetic variants in these transporters contribute to interindividual variability of a wide range of drugs.

AREAS COVERED

This review discusses the current literature on the impact of genetic variants in ABCB1, ABCG2 as well as ABCC1, ABCC2, and ABCC3 on pharmacokinetics and drug response. The aim was to evaluate if results from recent studies would increase the evidence for potential clinically relevant pharmacogenetic effects.

EXPERT OPINION

Although enormous efforts have been made to investigate effects of ABC transporter genotypes on drug pharmacokinetics and response, the majority of studies showed only weak if any associations. Despite few unique results, studies mostly failed to confirm earlier findings or still remained inconsistent. The impact of genetic variants on drug bioavailability is only minor and other factors regulating the transporter expression and function seem to be more critical. In our opinion, the findings on the so far investigated genetic variants in ABC efflux transporters are not suitable as predictive biomarkers.

[Pharmacogenomics: precision tool in routine prescription]

Pharmacogenomics is an emerging tool to improve the efficacy and safety of drug treatment through the DNA analysis in the genes related to drug concentrations (pharmacokinetics) and drug actions (pharmacodynamics). Clinicians need to integrate the genomic data in their benefit-risk assessment and then provide the right drug to the right patient at the right time. This tool can help to prevent an ineffective treatment, select right dose and reduce adverse drug reactions that are common in the current practice under the trial-observation-adjustment model. Pharmacogenomics may have extensive impacts on unique paediatric patients to enhance a better relationship between medical professionals and affected children or their guardians and to improve the drug compliance. Clinicians should embrace the advancements in pharmacogenomics and actively participate in clinical research to identify the ancestor-related alleles and develop the population-specific gene panel. It will allow patients to enjoy more achievements in pharmacogenomics by implementing it in first line clinical practice.

A prospective observational study of pediatric opioid prescribing at postoperative discharge: how much is actually used?

PURPOSE

Research describing opioid misuse in children after surgery currently describes single specialties, short follow-up, and heterogeneous data not conducive to comparative discussion. Our primary objective was to quantify opioids prescribed to pediatric surgical patients on discharge from hospital. Secondary objectives were quantifying opioids remaining unused at four-week follow-up, and family attitudes to safe storage and disposal.

METHODS

We conducted a prospective observational study under counterfactual consent with telephone follow-up at four weeks of children who had undergone a surgical procedure and filled an opioid prescription at The Hospital for Sick Children, Toronto, ON, Canada. Exclusion criteria included opioid use within the previous six months, history of chronic pain, or discharge to a rehabilitation facility. Pre- and post-discharge prescribing, dispensing, and consumption data were collected prospectively in addition to parental reports of home opioid use. Opioid-dosing was converted to oral morphine milligram equivalents (MME).

RESULTS

There were 8,672 MMEs prescribed to 110 patients. Twenty-one patients were lost to follow-up, accounting for 1,416 MME. Of the remaining 7,256 MME, 67% went unused. At follow-up, 78% of unused opioid remained in the home. Most opioids were stored in an easily accessible location in the home.

CONCLUSION

These findings confirm overprescribing of opioids to pediatric surgical patients. Families tend not to return opioids that exceed post-discharge analgesic requirements at home and many of the reported disposal methods are unsafe. We recommend future studies focus on optimizing opioid prescriptions to meet, but not excessively surpass, home pain management requirements, and to encourage safe opioid disposal/return methods.

TRIAL REGISTRATION

www.clinicaltrials.gov (NCT03562013); registered 7 June, 2018.

[Medications in breastfeeding: what evidence is there?]

Breastfeeding plays a fundamental role in the benefits for the health of the newborn child and the nursing mother. The use of medications during breastfeeding is a relevant issue, by virtue of the frequent need for pharmacological treatment in the postpartum period. The scope of this article was to conduct a review of the literature regarding the efficacy and safety of medications used during the breastfeeding period. A search was conducted in the PubMed (National Library of Medicine), ScienceDirect and Biblioteca Virtual em Saúde (BVS) databases for articles published in Portuguese, English and Spanish in the period from 1981 to 2016. This review discusses the risk of the use of medications during lactation and the effects that they may have on the breastfed infant. Few medications are contraindicated and others require care due the risk of adverse effects on breastfed infants or in the suppression of breast milk volume. Therefore, the dissemination of updated information for the health professional to adequately assess the risks and the benefits of the use of medications during breastfeeding is of vital importance, thereby contributing to avoid early weaning.

A cost-effectiveness analysis of maternal CYP2D6 genetic testing to guide treatment for postpartum pain and avert infant adverse events

Mothers with a CYP2D6 ultrarapid metabolizer phenotype may expose their infants to risk of adverse events when taking codeine while breastfeeding, by producing more of the active metabolite, morphine. Pharmacogenetic testing may be a valuable tool to identify such mothers, but testing can be costly. The objective of the study was to determine the incremental costs of genotyping to avert neonatal adverse events during maternal pharmacotherapy. A cost-effectiveness analysis, using a decision model, was performed with a hypothetical cohort of prenatal subjects. Parameter estimates, costs and ranges for sensitivity analyses were ascertained from the literature and expert opinion. Sensitivity analyses were conducted to assess the robustness of the results. Probabilistic sensitivity analysis revealed an incremental cost-effectiveness (ICER) of $10 433 (Canadian dollars) for genotyping compared to no genotyping per adverse event averted. Results were sensitive to hospital admission costs. The ICER was lower when evaluating only subjects having caesarean deliveries or those from ethnic populations known to have a high prevalence of ultra-rapid metabolizers. Although genotyping to guide pharmacotherapy was not cost saving, the cost to avert an infant adverse event may represent good value for money in specific populations. With a growing demand for personalized medicine, these findings are relevant for decision makers, clinicians and patients.

The pharmacogenetics of opioid therapy in the management of postpartum pain: a systematic review

AIMS

Opioids are commonly prescribed for postpartum pain. Yet, providing adequate pain relief, while ensuring that the mother and her breastfeeding infant are protected from adverse events can be challenging. The objective of this systematic review was to identify the role of opioid pharmacogenetics in analgesia and adverse events among patients being treated for postpartum pain, along with their breastfeeding infants.

METHODS

A comprehensive search of the literature was conducted in seven databases on June 3-4, 2015. Two reviewers independently screened studies for eligibility, extracted data and evaluated study quality using the Newcastle-Ottawa Scale.

RESULTS

Among the 2082 papers retrieved from the search, 17 were included in the review. These 17 papers consisted of various study designs, opioids, polymorphisms and patient outcomes. This systematic review reveals that CYP2D6, OPRM1 A118G, UGT2B7 C802T and ABCB1 G2677AT may contribute to postpartum analgesia or adverse events.

CONCLUSION

These findings may assist in personalizing care for patients receiving opioids during the postpartum period.

Adverse drug reactions in neonates and infants: a population-tailored approach is needed

Drug therapy is a powerful tool to improve outcome, but there is an urgent need to improve pharmacotherapy in neonates through tailored prevention and management of adverse drug reactions (ADRs). At present, infants commonly receive off-label drugs, at dosages extrapolated from those in children or adults. Besides the lack of labelling, inappropriate formulations, (poly)pharmacy, immature organ function and multiple illnesses further raise the risk for ADRs in neonates and infants. Pharmacovigilance to improve the prevention and management of ADRs needs to be tailored to neonates and infants. We illustrate this using prevention strategies for drug prescription and administration errors (e.g. formulation, bedside manipulation, access), detection through laboratory signalling or clinical outlier data (e.g. reference laboratory values, overall high morbidity), assessment through algorithm scoring (e.g. Naranjo or population specific), as well as understanding of the developmental toxicology (e.g. covariates, developmental pharmacology) to avoid re-occurrence and for development of guidelines. Such tailored strategies need collaborative initiatives to combine the knowledge and expertise of different disciplines, but hold promise to become a very effective tool to improve pharmacotherapy and reduce ADRs in infants.

Sedating drugs and breastfeeding

QUESTION

If a mother takes a sedating drug during breastfeeding, will it cause central nervous system (CNS) depression in her breastfed baby?

ANSWER

In some cases (eg, with the use of codeine or oxycodone) sedating drugs will likely cause CNS depression in breastfed infants and in other cases (eg, with the use of benzodiazepines) they will likely not. Mothers using sedating drugs should monitor their breastfed infants for signs of CNS depression (eg, drowsiness; difficulty breathing, feeding, or latching; or cyanosis), paradoxical effects (eg, unusual excitement,irritability), or inadequate weight gain.

Endogenous opiates and behavior: 2013

This paper is the thirty-sixth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2013 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.

Tailored tools to improve pharmacotherapy in infants

INTRODUCTION

Extensive within-population variability is the essence of neonatal pharmacology. Despite this, infants remain one of the last therapeutic orphans. Together with additional legal initiatives, tailoring of already available tools (modeling, covariates, pharmacovigilance) may significantly improve pharmacotherapy in infants.

AREAS COVERED

Modeling approaches that hold the promise to improve pharmacotherapy in infants are between-compound extrapolation for compounds that undergo the same route of elimination and integration of time-varying physiology to adapt for the fast maturational changes. Besides these maturational covariates (size, age), newly emerging covariates relate to novel treatment modalities (extracorporeal circulation, hypothermia), environmental issues (microbiome, critical illness) or pharmacogenetics. All these covariates interact with the maturational variation. Finally, pharmacovigilance also needs to be tailored to the characteristics of this population. This relates to preventive strategies, signal detection and assessment of causality.

EXPERT OPINION

Knowledge on pharmacotherapy in infants is lagging. Tailoring available tools to the specific characteristics (maturation) and clinical needs (newly emerging covariates) of infants is feasible but needs creativity and a multidisciplinary collaboration between modelers, academia, clinical researchers and, obviously, the public, including parents.

Pharmacogenomics and adverse drug reactions in children

Adverse drug reactions are a common and important complication of drug therapy in children. Over the past decade it has become increasingly apparent that genetically controlled variations in drug disposition and response are important determinants of adverse events for many important adverse events associated with drug therapy in children. While this research has been difficult to conduct over the past decade technical and ethical evolution has greatly facilitated the ability of investigators to conduct pharmacogenomic studies in children. Some of this research has already resulted in changes in public policy and clinical practice, for example in the case of codeine use by mothers and children. It is likely that the use of pharmacogenomics to enhance drug safety will first be realized among selected groups of children with high rates of drug use such as children with cancer, but it also likely that this research will be extended to other groups of children who have high rates of drug utilization and as well as providing insights into the mechanisms and pathophysiology of adverse drug reactions in children.

Clinical Pharmacogenetics Implementation Consortium guidelines for cytochrome P450 2D6 genotype and codeine therapy: 2014 update

Codeine is bioactivated to morphine, a strong opioid agonist, by the hepatic cytochrome P450 2D6 (CYP2D6); hence, the efficacy and safety of codeine are governed by CYP2D6 activity. Polymorphisms are a major cause of CYP2D6 variability. We summarize evidence from the literature supporting this association and provide therapeutic recommendations for codeine based on CYP2D6 genotype. This document is an update to the 2012 Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines for CYP2D6 genotype and codeine therapy.

Pharmacogenomics in children

Historically genetics has not been considered when prescribing drugs for children. However, it is clear that genetics are not only an important determinant of disease in children but also of drug response for many important drugs that are core agents used in the therapy of common problems in children. Advances in therapy and in the ethical construct of children's research have made pharmacogenomic assessment for children much easier to pursue. It is likely that pharmacogenomics will become part of the therapeutic decision making process for children, notably in areas such as childhood cancer where the benefits and risks of therapy are considerable.