Pharmacokinetic and Adsorptive Analyses of Administration of Oral Voriconazole Suspension via Enteral Feeding Tube in Intensive Care Unit Patients.

For intensive care unit (ICU) patients, injectable voriconazole (VRCZ) is difficult to use because the patients often develop acute kidney injury. Since many ICU patients have consciousness disturbance, oral ingestion of tablet formulation is also difficult, and administration of a suspension via enteral feeding tube is required when using VRCZ. In this study, we investigated the in vitro adsorption property of oral VRCZ to feeding tube and performed pharmacokinetic analysis of VRCZ prepared by powdering and simple suspension for ICU patients. VRCZ was tube-administered to five ICU patients at a loading dose of 300 mg and plasma VRCZ concentrations before and at 1, 2, 4, 8, 12 h after the first dose were measured using HPLC. Pharmacokinetic parameters were calculated by non-compartmental model analysis. The recovery rate of VRCZ after infusion of the suspension through feeding tube was 89.8 ± 8.3%, but the cumulative rates after the first and second re-infusion were 102.7 ± 20.7 and 99.3 ± 10.3%, respectively, suggesting almost no residual drug in the tube after re-infusion. Metabolic phenotype was extensive metabolizer (EM) in two patients and intermediate metabolizer (IM) in three patients. The values of total clearance (CLtot/F) calculated by moment analysis were 0.51 and 0.55 L/h/kg in two EM patients, and 0.09, 0.29 and 0.31 L/h/kg in three IM patients. The CLtot/F was apparently lower in IM patients compared to EM. In conclusion, powdered and suspended VRCZ administered via enteral feeding tube showed pharmacokinetics depending on CYP2C19 gene polymorphism, similar to that observed in usual oral administration.

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.

Administration of Kampo medicine through a tube at an advanced critical care center.

n emergency and critical care medical centers, tube administration is employed for patients who have difficulty swallowing oral drugs owing to decreased consciousness or mechanical ventilation. However, tube clogging due to drug injection is a concern. We compared the crushing method with the simple suspension method for the passage of amlodipine, an antihypertensive drug, in combination with rikkunshito, which has been used to treat upper gastrointestinal disorders such as functional dyspepsia and gastroesophageal reflux in emergency and critical care medical centers, to ascertain the effect of Kampo products on the passage of other drugs during tube administration. When the crushing method was employed, poorly water-soluble solid products were formed, while a uniformly dispersed suspension was obtained using the simple suspension method. In addition, the passage rate of amlodipine through the tube was 64% and 93% in the crushing and simple suspension methods, respectively, thereby indicating that the simple suspension method provided more favorable than the crushing method. The results of this study suggested that the passage rate of amlodipine for patients who received Kampo products concurrently was higher when the simple suspension method was used, and an appropriate drug amount might well be able to administered to patients using this method. J. Med. Invest. 65:32-36, February, 2018.

Examination Regarding the Simple Suspension Method using Oral Anticancer Drugs / 社会薬学

To administer oral anticancer drugs safely, the simple suspension method has been introduced in many hospitals. Therefore, concerning drugs for which it is unclear whether or not this method is applicable, testing must be able to be conducted at any time. In this study, we investigated 20 oral anticancer drugs to expand information on the application of the simple suspension method. Disintegration/suspension and permeability tests were conducted, as described in the 3rd version of the Tube Administration Handbook for Oral Drugs. All products were disintegrated/suspended after 10 minutes. On permeability tests, there was no residue in any tube for tubal feeding. On the final evaluation, the products were regarded as suitable (grade 1). Bicalutamide tablets (80 mg, TCK and KN), which were analyzed in this study, were regarded as suitable (grade 1) on the final evaluation. On the other hand, the simple suspension method is not applicable for a brand-name drug, Casodex^® tablets (80 mg). This may be related to the different additives. Furthermore, the results suggest that, even when the simple suspension method is not applicable for a brand-name drug, it may become applicable for generic drugs. This may provide a new merit for promoting the use of generic drugs.

Creating a List of Oral Anticancer Drugs using the Simple Suspension Method for Appropriate Therapy / 社会薬学

In cancer chemotherapy, it is very important to take into account the patient’s background. In recent years, a simple suspension method has attracted increased attention as a method that prevents changes in the stability and safety of various drugs. However, of 135 oral anticancer drugs, only 28 have been examined using this method, as of April 2013. In this study, we carefully investigated whether 53 oral anticancer drugs could be adapted to the simple suspension method, except for the 28 drugs that had already been previously reported. The results showed that most of these oral anticancer drugs could be adapted to the simple suspension method. Of seven drugs that were not adapted, six were generic drugs. In addition, it was clear that the evaluation of bicalutamide tablets was significantly different from our expected results. In conclusion, we were able to qualitatively assess all 53 oral anticancer drugs. This is equivalent to half of 107 untested drugs. These results provide useful information to cancer patients using oral anticancer drugs prepared using the simple suspension method.