Quantitative analysis of drug losses administered via nasogastric tube – In vitro study

Evaluation of in vitro dissolution profiles of modified-release metoprolol succinate tablets crushed using mortar and pestle technique

PURPOSE

Clinical practice guidelines advise against crushing modified-release dosage forms. Metoprolol succinate modified-release (MS-MR) tablets are commonly crushed in clinical practice to facilitate administration to patients with swallowing difficulties or using feeding tubes. To date, the effect of this practice remains unexplored. The in vitro effects of crushing commercially available MS-MR tablets were explored using a holistic approach.

METHODS

Dissolution profiles of crushed versus whole MS-MR tablets were compared. Tablets were crushed to powder state using pragmatic method mimicking hospital practices. For standardization purposes, the same operator, duration (60 seconds), hand, and mortar-pestle apparatus were used. Dissolution studies were conducted per U.S. Pharmacopeia at pH 1.2, pH 4.5, and pH 6.8 with USP apparatus 2 (paddle) at rotation speed of 50 rpm at 37±0.5 °C in 500 mL dissolution media. Samples were withdrawn at predetermined time points. Percent drug dissolved was measured by validated UV-vis Spectrophotometry. Comprehensive analysis of the dissolution data was conducted using model-independent, model-dependent, and ANOVA-based approaches (SPSS v.23 at α=0.05). Similarity (f2) and difference (f1) factors were calculated to compare the dissolution profiles between crushed (CT) and whole tablets (WT). Goodness of fit (GOF) analysis examined the compliance between in vitro dissolution behaviors and several drug release models. Model selection was based on GOF plots, Akaike criteria and adjusted coefficient of determination (R2adj). Imaging and particle size distribution analysis were conducted to examine associated surface and morphologic changes.

RESULTS

The dissolution profiles were not similar at pH 4.5 (f2=45.43, f1=18.97) and pH 6.8 (f2=31.47, f1=32.94). CT best fitted with Higuchi (pH 1.2: R2adj=0.9990), Weibull (pH 4.5: R2adj=0.9884), and Korsmeyer-Peppas (pH 6.8: R2adj=0.9719). Contrastingly, WT best fitted with Hopfenberg (pH 1.2: R2adj=0.9986), logistic (pH 4.5: R2adj=0.9839) and first-order (pH 6.8: R2adj=0.9979) models. A significant difference in the dissolution profiles was found between CT and WT using multivariate analysis of variance per time points and between the tablet forms (p=0.004). This was confirmed by unparalleled dissolution profiles. Crushing resulted in variations in particle size and surface morphological changes to the micropellets.

CONCLUSION

Crushing practices change the dissolution profile of MS-MR tablets by deforming the surface morphology of embedded micropellets. Amounts of drug dissolved between CT and WT were not the same at the compared time points across gastrointestinal pH ranges. This suggests potential clinical impact on plasma-concentration profiles of critically ill patients using feeding tube.

Enteral Delivery of Pravastatin Sodium Tablets: Effect of Compounding into a Liquid Form and Co-Administration of Enteral Nutrition

BACKGROUND

Compounding solid oral dosage forms into liquid preparations is a common practice for administering drug therapy to patients with swallowing difficulties. This is particularly relevant for those on enteral nutrition, where factors such as the administration procedure and co-administration of enteral nutrition play crucial roles in effective drug delivery. Due to the limited studies focused on this practice, the impact of co-administered nutrition remains unclear.

METHODS

Pravastatin tablets were compounded into two liquid formulations and administered through three independent tubes for ten cycles. The drug amount was quantified upstream and downstream of the tubes both with and without different (fiber content) nutritional boluses.

RESULTS

The compounding procedure did not lower the drug amount with respect to the original tablets. However, when the liquid formulation was pumped through the tubes, a statistically significant reduction in the pravastatin administered (between 4.6% and 11.3%) was observed. The co-administration of different nutritional boluses or the compounding procedure did not affect the general results.

CONCLUSIONS

Pravastatin loss appears unavoidable when administered via the enteral tube. Although, in this case, the loss was of limited clinical relevance, it is important not to underestimate this phenomenon, especially with drugs having a narrow therapeutic index.

In vitro optimization of crushed drug-sensitive antituberculosis medication when administered via a nasogastric tube

IMPORTANCE

The incidence of tuberculosis (TB) in intensive care units (ICUs) can be as high as 3% in high-burden settings, translating to more than 7,500 patients admitted to the ICU annually. In resource-limited settings, the lack or absence of intravenous formulations of drug-sensitive antituberculosis medications necessitates healthcare practitioners to crush, dissolve, and administer the drugs to critically ill patients via a nasogastric tube (NGT). This off-label practice has been linked to plasma concentrations below the recommended target concentrations, particularly of rifampicin and isoniazid, leading to clinical failure and the development of drug resistance. Optimizing the delivery of crushed drug-sensitive antituberculosis medication via the NGT to critically ill patients is of utmost importance.

Current Insights into Diagnosing and Treating Neurotuberculosis in Adults

Neurotuberculosis has the highest morbidity and mortality risk of all forms of extrapulmonary tuberculosis (TB). Early treatment is paramount, but establishing diagnosis are challenging in all three forms of neurotuberculosis: tuberculous meningitis (TBM), spinal TB and tuberculomas. Despite advancements in diagnostic tools and ongoing research aimed at improving TB treatment regimens, the mortality rate for neurotuberculosis remains high. While antituberculosis drugs were discovered in the 1940s, TB treatment regimens were designed for and studied in pulmonary TB and remained largely unchanged for decades. However, new antibiotic regimens and host-directed therapies are now being studied to combat drug resistance and contribute to ending the TB epidemic. Clinical trials are necessary to assess the effectiveness and safety of these treatments, addressing paradoxical responses in neurotuberculosis cases and ultimately improving patient outcomes. Pharmacokinetic-pharmacodynamic analyses can inform evidence-based dose selection and exposure optimization. This review provides an update on the diagnosis and treatment of neurotuberculosis, encompassing both sensitive and resistant antituberculosis drug approaches, drawing on evidence from the literature published over the past decade.

A systematic approach for assessing the suitability of enteral feeding tubes for the administration of controlled-release pellet formulations

Enteral nutrition plays an important role for patients who are unable to properly swallow food. In such patients, enteral feeding tubes are often used, through which food, but often also oral medications, are administered. However, this can pose the risk of tube clogging. Compared to the administration of crushed tablets, multiparticulate dosage forms are often considered easier to administer and furthermore have the advantage of enabling the administration of even controlled-release preparations. The objective of this systematic study was to identify tube- and formulation-related factors that contribute to successful administration of coated pellet formulations via a variety of commercially available feeding tube devices. The suitability of enteral feeding tubes for the administration of controlled-release pellet formulations that differed in size and type of starter core and functional coating was investigated in a stepwise approach using a novel in vitro setup. Results of the study indicate that pellet diameter and inner diameter of the feeding tube are by no means reliable parameters for estimating the tube's suitability for pellet administration, but that many other tube and formulation-related factors and combinations thereof must be considered to ensure safe and effective drug administration via enteral feeding tubes.

A Safe Way to Administer Drugs Through a Nutrition Tube-The Simple Suspension Method

The simple suspension method (SSM), developed by Kurata in 1997, is a way to suspend tablets and capsules in warm water for decay and suspension prior to their administration. This method is safe and has various advantages such as the avoidance of tube clogging and the loss of the drug. This study aimed to investigate whether a higher percentage of commonly used drugs could pass through nutrition tubes effectively using SSM, relative to that using the conventional crushing method. A tablet or capsule was inserted into a 20 mL syringe with warm water (at 55 °C). After 10 min, it was shaken in the syringe. The suspension liquid was injected into tubes of the following sizes: 8 Fr, 10 Fr, 12 Fr, 14 Fr, 16 Fr, and 18 Fr. A total of 3686 tablets and 432 capsules that are frequently used in Japan were tested. Using SSM, 3377 (91.6%) tablets and 359 (83.1%) capsules disintegrated within 10 min and passed through the tube without clogging it in the tube passage test. With the conventional crushing method, 2117 tablets (57.4%) and 272 capsules (63.0%) could be crushed. SSM reduced the risk of tube clogging and drug loss with more drugs than that with the conventional crushing method. The number of drugs indicated for administration by SSM is greater than that indicated by the conventional crushing method. Further studies are needed to consider its utility compared to conventional methods for dysphagia patients in clinical settings.

Data on compounding lopinavir and ritonavir suspension for non-cooperative COVID-19 patients

The COVID-19 outbreak is now one of the most critical crises to manage for most of national healthcare systems in the world. The situation is complicated by the absence of vaccines and authorized pharmacological treatments, except for remdesivir. In this context, many medicaments, including different Ebola and HIV antivirals, are used off-label in the hospital wards as life-treating medicines for COVID-19 patients. Authorized medicaments manipulation is sometimes necessary because they are not always formulated to be administered to non-cooperative patients or they are in shortage. It is this the case of the fixed combination of lopinavir/ritonavir, which was extensively used in the first phase of the outbreak inducing a shortage of the oral solution available in the EU market. This work provides data on size distribution, osmolarity other than drug chemical stability of a lopinavir/ritonavir extemporaneous preparation made by using the solid dosage form (i.e., tablet) available on the market as drug source. The reported data indicate that such preparation is suitable to be delivered through a nasogastric tube, and enough stable for two weeks from the preparation at room temperature.

Study of the More Suitable Drugs and Dosage Forms for Administration to Newborn Infants via Feeding Tube Using the Collection Rate as an Indicator

The dosages of drugs in newborn infants are small. Small dose necessitate consideration of the loss of drug when administered via feeding tube. In this study, we conducted a tube administration test for seven kinds of antiepileptic drugs and two kinds of potassium supplements using a neonatal feeding tube and investigated the drug loss using the collection rate. We also studied the differences in collection rates among different dosage forms and drugs to determine the more suitable dosage forms and drugs. We investigated three dosage forms: powder, fine granules or dry syrup (powdery form) drugs, powdery form drugs that have been pulverized (pulverized powdery forms), and pulverized tablets. Additionally, we investigated two potassium supplements to determine which was more suitable: potassium L-aspartate and potassium gluconate. For topiramate, only the powdery form caused tube obstructions; the collection rates of the pulverized powdery form and pulverized tablets were > 90%. All antiepileptic drugs other than topiramate that were tested had collection rates of about > 90%. Considering stability and pharmacokinetics, the more suitable dosage form for topiramate is pulverized tablets, whereas the more suitable dosage form for other antiepileptic drugs is powdery form. Collection rate of potassium gluconate was higher than that of potassium L-aspartate. The current study, which indicates that potassium gluconate powdery form is the more suitable drug, presents the more suitable dosage form and drug for administration via feeding tube to newborn infants. These results show that it is essential to evaluate passage through the tube using the collection rate.

Potassium canrenoate compounding for administration via enteral feeding tubes: a physical and microbiological stability study

Background

Swallowing difficulties are arising in an increasing number of patients, especially in elderly people. When deglutition ability is completely compromised, enteral administration of a drug via feeding tubes is used. Licensed pharmacists have to compound the original solid forms to enable this drug therapy.

Objectives

To evaluate the possibility of compounding original commercial tablets to produce a liquid formulation suitable for administering via a feeding tube.

Methods

Two liquid formulations containing potassium canrenoate 5 mg/mL were prepared: a standard solution obtained by solubilising raw material and an extemporaneous preparation obtained by dissolving film-coated 100 mg tablets. Spectrophotometric determinations (UV range) of the drug established chemical stability of the analyte up to 60 days. Samples were tested for microbial growth. Gravimetric quantifications of liquid formulations were used to check any weight loss during the different steps before enteral administration.

Results

UV data confirmed the chemical stability of potassium canrenoate up to 60 days. Samples showed no microbial growth. A higher weight loss was recorded in extemporaneous preparations than in the standard solution (10.7% vs 7.6%) according to the gravimetric quantification.

Conclusion

It is possible to compound the original tablets into a liquid formulation suitable for administration via a feeding tube.

Dosage form modification and oral drug delivery in older people

Many people cannot swallow whole tablets and capsules. The cause ranges from difficulties overriding the natural instinct to chew solids/foodstuff before swallowing, to a complex disorder of swallowing function affecting the ability to manage all food and fluid intake. Older people can experience swallowing difficulties because of co-morbidities, age-related physiological changes, and polypharmacy. To make medicines easier to swallow, many people will modify the medication dosage form e.g. split or crush tablets, and open capsules. Some of the challenges associated with administering medicines to older people, and issues with dosage form modification will be reviewed. Novel dosage forms in development are promising and may help overcome some of the issues. However, until these are more readily available, effective interdisciplinary teams, and improving patient health literacy will help reduce the risk of medication misadventures in older people.

Drug loss while crushing tablets: Comparison of 24 tablet crushing devices

This study investigated 24 tablet crushing devices for drug loss using different methods to recover the crushed tablet. 24 devices were compared: 3 with disposable cups, 6 with disposable bags, 12 without separate vessels and 3 types of mortar and pestle. One paracetamol tablet was crushed and recovered by tapping the powder out. Where appropriate, depending on crusher size and manufacturer instructions, the powder was also recovered by mixing with water or food. Paracetamol recovery (quantity that can be delivered to a patient) and leftover (quantity remaining in the device) were measured using a validated UV method and the entire experiment was replicated 3 times. Drug recovery ranged from 86.7-98.1% when the crushed tablet was tapped out of the crushers (average loss 5.8%). Significant losses were measured for 18 crushers, particularly manually operated hand-twist crushers with a serrated crushing surface, and some devices with disposable bags or cups. Rinsing the crushed powder with water once resulted in an average of 24.2% drug loss, and this was reduced to 4.2% after a second rinse. If crushing is unavoidable, maximizing medication delivery to the patient is essential. Rinsing twice resulted in similar paracetamol recovery to tapping the powder out; however only water rinses have the potential for direct consumption by the patient, minimizing drug loss across the entire crushing and transfer process.

Intensive care unit nurses' knowledge of medication administration via enteral tubes

BACKGROUND

Medication administration via enteral tubes is a complex and key application for which nurses in intensive care units are responsible.

AIM

The aim of this study was to evaluate drug administrations via enteral tubes by nurses in intensive care units.

METHODS

This research was conducted using a descriptive and cross-sectional research design. The study was conducted with 289 nurses at intensive care units in hospitals in İzmir, Turkey. The data of the study were collected with the 'Sociodemographic Information Form' and the 'Enteral Medication Administrations Questionnaire', which was designed in accordance with the literature and consists of questions on interventions before, during and following medication administrations via enteral tubes.

RESULTS

It was found that more than half the nurses (62.3%) use nasogastric tubes for medication administrations and that all of them use the enteral way for the administration of medications in the form of tablets, while 58.8% use this method to administer the medications in the form of enteric-coated tablets. It was determined that approximately half the nurses (52.6%) apply more than one medication separately, and a majority (84.1%) use tap water to wash the enteral tube.

CONCLUSIONS

Enteral medication administration practices are inconsistent. Some nurses use unsafe practices and may therefore compromise patient care.

RELEVANCE TO CLINICAL PRACTICE

Conduction of education programmes on medication administration via enteral tubes for intensive care unit nurses is important in improving nurses' knowledge.

In Vitro Evaluation of Eslicarbazepine Delivery via Enteral Feeding Tubes

Purpose: The feasibility of preparing an eslicarbazepine acetate suspension using Aptiom tablets for administration via enteral feeding tubes was evaluated. Methods: Eslicarbazepine acetate suspension (40 mg/mL) was prepared using Aptiom tablets after optimizing the tablet crushing methods and the vehicle composition. A stability-indicating high-performance liquid chromatography (HPLC) method was developed to monitor the eslicarbazepine stability in the prepared suspension. Three enteric feeding tubes of various composition and dimensions were evaluated for the delivery of the suspensions. The suspension was evaluated for the physical and chemical stability for 48 hours. Results: The reproducibility and consistency of particle size reduction was found to be best with standard mortar/pestle. The viscosity analysis and physical stability studies showed that ORA-Plus:water (50:50 v/v) was optimal for suspending ability and flowability of suspension through the tubes. The developed HPLC method was found to be stability indicating and suitable for the assay of eslicarbazepine acetate in the prepared suspension. The eslicarbazepine concentrations in separately prepared suspensions were within acceptable range (±3%), indicating accuracy and reproducibility of the procedure. The eslicarbazepine concentrations in suspensions before and after delivery through the enteric feeding tubes were within acceptable range (±4%), indicating absence of any physical/chemical interactions of eslicarbazepine with the tubes and a successful delivery of eslicarbazepine dosage via enteric feeding tubes. The stability study results showed that eslicarbazepine concentration in the suspension remained unchanged when stored at room temperature for 48 hours. Conclusion: The study presents a convenient procedure for the preparation of a stable suspension of eslicarbazepine acetate (40 mg/mL) using Aptiom tablets, for administration via enteral feeding tubes.

Technological Evaluation of Emulsions Containing The Volatile Oil from Leaves of Plectranthus Amboinicus Lour

BACKGROUND

Plectranthus amboinicus Lour is a species which is widespread throughout tropical countries where it is widely used against respiratory tract disorders such as bronchodilator, antitussive, and expectorant conditions.

OBJECTIVE

This study aims to characterize the essential oil of P. amboinicus (PaEO) and produce and evaluate emulsions containing PaEO.

MATERIALS AND METHODS

The essential oil was characterized by physical-chemical analyses for density, refractive index, 90% ethanol solubility, color, appearance, and identification by gas chromatography coupled to mass spectrometry detection. The emulsions were prepared following a hydrophile-lipophile balance [HLB] spreadsheet design from two nonionic surfactants (Span 80^® and Tween 20^®) producing HLB values ranging from 4.3 to 16.7. The products were stored at room temperature at 5°C. The emulsion stabilities were tested both in the long and short-term.

RESULTS

The PaEO was obtained by steam distillation and the total extraction was reached after 3 hours yielding of 0.2% (w/w). This essential oil was characterized by physicochemical analyses for density [1.5 g.ml^-1], refraction index [0.9167], ethanol 90% solubility [1:2], color, and appearance (yellow/clear). Nineteen components were identified in the oil, among them the sesquiterpenes: carvacrol [33.50%], p-cymene [28.20%] and γ-terpinene [14.77%]. The emulsions obtained successfully showed, for the first time, HLB values for essential oils from Plectranthus amboinicus [15.7].

CONCLUSION

The experimental data shows a relationship between HLB values of the surfactant mixtures contributing to the emulsified systems production containing phytopharmaceuticals. Such an approach is of great importance to the development of lipid carriers for therapeutic drugs.

SUMMARY

The essential oil from leaves of Plectranthus amboinicus was extracted by steam distillation and characterized.The emulsions containing essential oil were produced and the stability was performed in the short and long term.The critical hydrophilic-lipophilic balance (HLB) of the essential oil was 15.7 and was achieved by the combination of surfactants (Tween 80^® and Span 20^®). Abbreviations used: PaEO: essential oil of P. amboinicus, HLB: hydrophilic-lipophilic balance, CI: Creaming Index, MET: micro-emultocrit technique.

Reflection on the Pharmaceutical Formulation Challenges Associated with a Paediatric Investigation Plan for an Off-Patent Drug

In Europe, the development of pediatric medicines for new patent protected products is mandatory and applicants are required to submit a Paediatric Investigation Plan (PIP) to the regulatory authorities. The process is voluntary for off-patent medicines and despite the availability of incentives, there is still a huge unmet need for the development of off-patent pediatric medicines. The aim of the EU grant funded "Labeling of Enalapril from Neonates to Adolescents" (LENA) project is to develop a new pediatric dosage form of the off-patent drug enalapril, for the treatment of heart failure in patients aged from birth to 18 years. This article provides an overview of some of the key formulation challenges that were faced during the product development programme and PIP process, including selection of dosage form and excipients, methodology for administration of the product and evaluation of patient acceptability.