Applied pharmacokinetics to improve pharmacotherapy in neonatal and paediatric intensive care units: focus on correct dose selection.

Drug dosing and exposure throughout childhood are constantly affected by maturational changes like weight, age or body surface area. In neonatal and paediatric intensive care units (NICU and PICU, respectively), drug dosing and exposure are further impacted by non-maturational changes. These changes are related to factors such as sepsis, cardiac failure, acute kidney injury, extracorporeal circuits or drug-drug interactions (DDIs) resulting from polypharmacy.This potentially complex situation may alter drug pharmacokinetics to result in greater-than-usual intrapatient and interpatient drug exposure variability. These effects may call for individual dosage adjustments. Dosage adjustments may apply to both loading doses or maintenance doses, which should be used as appropriate, depending on the specific characteristics of a given drug. Phenobarbital and vancomycin dosing are hereby used as illustrations.To optimise dose selection in NICU/PICU settings, we suggest to consider therapeutic drug monitoring integrated in model-informed precision dosing, and to familiarise oneself with existing paediatric drug formularies as well as DDI databases/search engines. Paediatric clinical pharmacologists and pharmacists can hereby guide clinicians with no prior experience on how to properly apply these data sources to day-to-day practice in individual patients or specific subpopulations of NICU or PICU patients.

A Callout for International Collaboration. Reply to Giger, E.V.; Tilen, R. Comment on "Shaniv et al. Neonatal Drug Formularies-A Global Scope. Children 2023, 10, 848".

We are very grateful that the global-scope paper on neonatal drug formularies has received a relevant amount of interest from the readership of the journal [...].

Neonatal Drug Formularies-A Global Scope.

Neonatal drug information (DI) is essential for safe and effective pharmacotherapy in (pre)term neonates. Such information is usually absent from drug labels, making formularies a crucial part of the neonatal clinician's toolbox. Several formularies exist worldwide, but they have never been fully mapped or compared for content, structure and workflow. The objective of this review was to identify neonatal formularies, explore (dis)similarities, and raise awareness of their existence. Neonatal formularies were identified through self-acquaintance, experts and structured search. A questionnaire was sent to all identified formularies to provide details on formulary function. An original extraction tool was employed to collect DI from the formularies on the 10 most commonly used drugs in pre(term) neonates. Eight different neonatal formularies were identified worldwide (Europe, USA, Australia-New Zealand, Middle East). Six responded to the questionnaire and were compared for structure and content. Each formulary has its own workflow, monograph template and style, and update routine. Focus on certain aspects of DI also varies, as well as the type of initiative and funding. Clinicians should be aware of the various formularies available and their differences in characteristics and content to use them properly for the benefit of their patients.

Effects of particle size and surface chemistry on plastic nanoparticle transport in saturated natural porous media.

Plastic nanoparticles (PNPs) are considered contaminants of emerging concern, but little information is available on their transport behavior in the soil-water environment, as well as their behavior relative to metal and other carbon-based nanoparticles. Here we show that size and surface functional groups affect the transport of polystyrene nanoparticles (PS-NPs) through saturated soil. Unmodified 110 nm and 50 nm PS-NPs demonstrated similar transport patterns in soil. However, a maximum elution value of 90% from the soil was found for the 50 nm PS-NPs, compared to a maximum value of ∼45% for 110 nm PS-NPs. The breakthrough curve for 190 nm PS-NPs demonstrated a maximum elution value of 60% from the soil. PS-NPs with surface functional groups display different mobility profiles: carboxylated PS-NPs demonstrated a plateau of 40% elution from the soil, while aminated PS-NPs were eluted only in small amounts and showed a spike pattern of elution from the column. These findings are attributed to the effects of common soil constituents such as calcium cations and humic acids on the size and charge of the PS-NPs with surface functional groups. Overall, PS-NP mobility in soil can vary widely, depending on PNP properties such as size and surface chemistry, and on matrix properties, such as the type of porous medium and its composition. These findings suggest that knowledge of inherent characteristics (size, surface charge, surface functional groups) of PNPs are required to elucidate the behavior of such particles in soil-water environments, and predict the extent of contaminant spreading.

Therapeutic levetiracetam monitoring during pregnancy: "mind the gap".

BACKGROUND: Epilepsy is one of the most common chronic neurological conditions and its treatment during pregnancy is challenging. Levetiracetam (LEV) is an antiepileptic medication frequently used during pregnancy. Only a few small studies have been published on LEV monitoring during pregnancy, demonstrating decreased serum LEV levels during the first and second trimester; however, the most significant decrease was observed during the third trimester of pregnancy. In this study we aimed to evaluate LEV pharmacokinetics during different stages of pregnancy. METHODS: We followed up and monitored serum levels of pregnant women treated with LEV for epilepsy. RESULTS: Fifty-nine women with 66 pregnancies during the study period were included. The lowest raw LEV serum concentrations were observed during the first trimester. Compared with the pre-pregnancy period, raw serum concentration was lower by 5.76 mg/L [95% confidence interval (CI) (2.78, 8.75), p = 0.039] during the first trimester. Comparing the decrease in the first trimester with either the second or the third, no significant changes were observed (p = 0.945, p = 0.866). Compared with pre-pregnancy measurements, apparent clearance was increased by 71.08 L/day [95%CI (16.34, 125.83), p = 0.011] during the first trimester. About 30% of LEV serum levels during pregnancy were below the laboratory quoted reference range. CONCLUSIONS: Raw LEV serum levels tend to decrease during pregnancy, mainly during the first trimester contrary to previous reports. Monitoring of LEV serum levels is essential upon planning pregnancy and thereafter if pre-pregnancy LEV levels are to be maintained. However, more studies are needed to assess the correlation with clinical outcome.

Fatal and Near-Fatal Non-allergic Reactions in Patients with Underlying Cardiac Disease Receiving Benzathine Penicillin G in Israel and Switzerland.

Benzathine Penicillin G (BPG) is commonly used for treatment of penicillin-susceptible infections and secondary prevention of rheumatic fever. Death following administration of BPG is extremely rare-only a handful of cases have been described in the literature since the 1950's. In this case series from Israel and Switzerland, we describe nine cases of serious adverse reactions-six fatal reactions and three near-fatalities-occurring within minutes of receiving intramuscular BPG. Allergic reactions or faulty administration were not implicated in any of the cases; however, all patients had cardiac risk factors. This case series describes a relatively rare risk that should be borne in mind when prescribing BPG.

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.

Antiepileptic Drug Treatment in Community-Dwelling Older Patients with Epilepsy: A Retrospective Observational Study of Old- Versus New-Generation Antiepileptic Drugs.

INTRODUCTION: The use of antiepileptic drugs (AEDs) in older patients with epilepsy is challenged by polypharmacy and decreased drug elimination. Newer AEDs have a lower potential for drug interactions and are reported to be better tolerated by the elderly than old-generation AEDs. OBJECTIVE: The objective of this study was to evaluate AED use and the related adverse event rate in an outpatient cohort of older patients with epilepsy. METHODS: We retrospectively reviewed the computerized database and medical records of all the patients aged ≥60 years who visited our epilepsy outpatient clinic (Assaf Harofeh Medical Center, Zerifin, Israel) during a 4-year period from February 2012 to February 2016. In this study, phenytoin, valproic acid, carbamazepine, phenobarbital, clobazam, and clonazepam were defined as old-generation AEDs. Gabapentin, levetiracetam, lamotrigine, topiramate, oxcarbazepine, lacosamide, and perampanel were defined as new-generation AEDs. RESULTS: The study group included 115 patients aged 60-90 years (mean 70.5 ± 7.8 years), 70 (61%) of whom were men. Co-morbidities were present in 98.3% of the patients, including neuropsychiatric illnesses in 21.2%. Present medical treatment included new-generation AEDs in 49 (44.5%) and both old- and new-generation AEDs in 20 (18.2%) patients. The most commonly used current AEDs were phenytoin, gabapentin, levetiracetam, and lamotrigine. Adverse reactions mainly included fatigue and CNS-related symptoms, and were more frequent among patients treated with new-generation AEDs than in those treated with old-generation AEDs or a combination of old- and new-generation AEDs; however, these reactions were mostly related to levetiracetam treatment. The likelihood of levetiracetam-related adverse events was increased by slow levetiracetam titration [defined as a weekly dose increase of ≤250 mg/day in this study; odds ratio (OR) 16.35, 95% confidence interval (CI) 2.94-90.98], and by low- (OR 5.68, 95% CI 1.40-22.95) and high (OR 4.24, 95% CI 1.28-14.02) levetiracetam dosages compared with patients treated with lamotrigine or gabapentin. CONCLUSIONS: New-generation AEDs were administered to most of the patients in this outpatient clinic-based cohort of older patients with epilepsy. In order to decrease levetiracetam-related adverse events in this age group, we suggest that a slower titration rate (e.g., an increase of ≤125 mg/day each week) and lower maximal dosage (e.g., 1500 mg/day) of the drug should be considered.