# Stability and Dissolution Behavior Changes After Drug Compounding for Pediatric Cardiovascular Pharmacotherapy

## TL;DR

This study evaluates how crushing and storing pediatric cardiovascular drugs affects their stability and effectiveness over time.

## Contribution

The study provides the first evaluation of stability and dissolution behavior of compounded pediatric cardiovascular drugs in Japan.

## Key findings

- Five cardiovascular drugs showed no more than 10% change in ingredient content after 120 days of storage.
- No impurities above 0.01% were detected in any of the formulations.
- Dissolution rates remained unchanged across all storage conditions.

## Abstract

Background: Compounding is performed to adjust dosages and support medication for children. In Japan, tablets are crushed, diluted with lactose, and stored in bottles or sachets until use, but the stability and impact on dissolution of the ingredients after crushing have not been evaluated. Methods: Using a database established by the National Center for Child Health and Development in collaboration with 11 medical facilities, the status of tablet crushing was investigated. Commonly compounded drugs were selected as the target drugs. The selected drugs were sieved through a 500 μm mesh after crushing and diluted with lactose hydrate. The stability at 25 ± 2 °C/60 ± 5% relative humidity and the dissolution of the ingredients were evaluated after storing them for up to 120 days under the following conditions: (I) stored in a closed polycarbonate bottle (closed), (II) bottle opened once a day (in-use), or (III) stored in a laminated cellophane and polyethylene sachet (laminated). The changes in the ingredient content and dissolution behavior were evaluated in accordance with the Japanese Pharmacopoeia. Results: Five cardiovascular drugs (amlodipine besylate, carvedilol, propranolol hydrochloride, hydrochlorothiazide, and tadalafil) were selected as target drugs. No more than 10% change in ingredient content was observed for all five formulations compared to day 0. In addition, no related substances (impurities) were detected at more than 0.01%. There was no change in the dissolution rate of the samples after 120 days of storage under each storage condition. Conclusions: The five cardiovascular drugs commonly compounded for children in Japan maintained their pharmaceutical quality after compounding, even after long-term storage.