Quality attributes

Quality attributes

Important quality attributes of a solution dosage form include potency; physical, chemical, and biological stability; palatability; deliverability of the dose; and dosage uniformity. Physical stability refers to the lack of precipitation, change in color, or any other change in physical appearance or perception (e.g., viscosity or pain upon injection) of the dosage form. Chemical stability refers to the lack of unacceptable chemical degradation of the drug during the shelf life of the product under recommended packag-ing and storage conditions. The drug product must meet the predetermined requirements of minimum potency of the active pharmaceutical ingredient (API) and maximum concentration of known and unknown impurities. In addition, since most of the solutions are formulated in aqueous vehicle, special measures must be taken that they remain free of any microbial growth.

Palatability of the dosage form is usually enhanced by the use of sweeten-ers, flavors, and colorants. Additional taste masking approaches such as drug adsorption on an ion-exchange resin may be utilized for especially bitter or otherwise unpleasant tasting drugs. Deliverability of the dose refers to the ability to retrieve the labeled amount of liquid from the dispensed container under normal usage conditions. The uniformity of content of API in each dispensed unit dose is demonstrated for interdose variability within the doses dispensed from a given multidose container (bottle) and also for bottle-to-bottle uniformity in the concentration of the API. Viscosity of the formulation is an important determinant of its deliverability and uniformity of content.