Basics of compounding: compounding with hydrates and solvates

As a practitioner, a pharmacist must understand that the most important consideration before compounding a preparation should be confirmation of the purity and form of all ingredients used, especially active pharmaceutical ingredients. It should be determined whether the dose is based on the "base", "salt", or "ester" form, etc. Also, many of the ingredients used in compounding are solvates, hydrated, or have allowable water content in the powders, and for those ingredients, allowances must be made based upon the water content of the drug. It is vitally important to refer to the Certificate of Analysis for this information. A pharmacist how to properly package, store, and weigh the different ingredients used in compounding. This article, which represents the first of a series of articles, discusses how the presence of "water" can affect the strength of the final compounded preparation.