Preparation of emulsions and concentrates thereof. This invention relates to emulsions and concentrates thereof, for example, drug-containing formulations in liquid and dried forms, for example a syrup, a liquid concentrate, a powder or a tablet, and a process for their manufacture optionally including spray or freeze drying. Many compositions, e. However formulating products in emulsion form raises its own problems, for example the stability of the emulsion itself and of its components, and the increased volume of an emulsion relative to a concentrated, solid formulation results in increased storage and transport expense.
In the case for example of vitamin-containing compositions e. Vitamins in liquid dosage forms are easily degraded mainly due to the influence of temperature, moisture, oxygen, light and pH. The presence of other vitamins will also influence the degradation pattern of each individual vitamin which complicates the formulation task even further.
It is also important to realize that it is the stability of the most unstable component which determines the overall shelf-life of a product. Thus vitamin compositions generally contain more than the labelled amounts of certain vitamins to allow for degradation during storage and so meet the legal requirement that the vitamin content must be at least as high as indicated on the product label throughout the shelf-life of the product.
While vitamin degradation may thus be compensated for, to some extent, by use of an overage, the overage should desirably be relatively small otherwise doses received when using relatively fresh product would be well above the desired level.
The USP monograph thus sets out limits for the vitamin content in a liquid formulation which are undesirably wide from a legal and cost perspective. Much narrower limits are clearly desirable.
