Evaluation of compounded aqueous milbemycin oxime: issues with formulation potency and reproducibility

Objectives To determine the potency and reproducibility of milbemycin oxime when compounded as an aqueous suspension (20 mg/mL). Materials and Methods Preparation choice reflected current prescribing practices. Samples were acquired by prescription from two national veterinary compounding pharmacies...

Full description

Saved in:

Bibliographic Details
Published in:	Journal of small animal practice Vol. 60; no. 1; pp. 27 - 31
Main Authors:	Cochrane, Z. N., Berger, D. J., Viall, A. K., Schrunk, D., (Hans) Coetzee, J. F.
Format:	Journal Article
Language:	English
Published:	Oxford, UK Blackwell Publishing Ltd 01-01-2019 Wiley Subscription Services, Inc
Subjects:	Administration, Oral Animals Drug Compounding - veterinary Liquid chromatography Macrolides - analysis Pharmacy Prescription Drugs - analysis Reproducibility Reproducibility of Results Storage conditions
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Objectives To determine the potency and reproducibility of milbemycin oxime when compounded as an aqueous suspension (20 mg/mL). Materials and Methods Preparation choice reflected current prescribing practices. Samples were acquired by prescription from two national veterinary compounding pharmacies at three time points. Two different storage conditions were evaluated and sampled at four time points from the order date (day 7, 14, 21 and 28). Milbemycin oxime recovery was performed by solid‐phase extraction and concentration strength measured via high‐performance liquid chromatography. Results The average concentration on day 7 for Pharmacy A samples was 16.29 mg/mL [confidence interval (CI): 15.66 to 16.92] with a coefficient of variation (CV) = 11%, while for Pharmacy B it was 20.46 mg/mL (CI: 19.83 to 21.08) with CV = 22%. The mean decrease in concentration over 28 days for Pharmacy A was 22% (CI: 9% to 34%) while Pharmacy B was 18% (CI: 2% to 35%). Clinical Significance The compounded milbemycin oxime suspensions evaluated in this study deviated by more than 10% from their labelled strength in five of the six lots. Clinical efficacy of compounded milbemycin oxime suspensions remains unknown and the use of these products should be discouraged at this time.
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0022-4510 1748-5827
DOI:	10.1111/jsap.12907