Paediatric capsule compounding in hospital practices: by weight or by volume?

Abstract

ObjectiveCapsule compounding is common for paediatric patients. In Europe, pharmacists often use a volume-based method whereas, in the USA, the weight-based method prevails. These two methods should be compared in order to help hospital pharmacists to make their choice.MethodsWe evaluated the difference between the volume-based method and the weight-based method with 10 mg spironolactone capsules. Six independent batches were made with each technique and their conformity was evaluated with a high-performance liquid chromatography assay.ResultsThe weight-based method showed superiority over the volume-based method for the following parameters: spironolactone content homogeneity, total weight content homogeneity, batch reproducibility and batch conformity. No differences were seen in spironolactone content between the two methods, but an overall trend towards underweighing the excipient was found with the volume-based method.ConclusionsCapsule compounding with the weight-based method increases the quality of the resulting formulation. The weight-based method requires knowledge of the galenic parameters of the active pharmaceutical ingredient and excipients, but should be preferred to the volume-based method.

Low-dose erythromycin in pediatrics: Formulation and stability of 20 mg hard gelatin capsules

“…Three experimental batches of 50 capsules containing 20 mg of erythromycin were formulated with using a weight-based method. Traditionally, our capsules were compounded with a volume-based method, but recent findings have encouraged us to use a weight-based method for hospital preparations [23]. First, the tapped density of the erythromycin/cellulose mixture was found to be equal to 0.460 g.mL -1 .…”