IMPROVEMENT OF DRUG PERFORMANCE BY THE USE OF SOME ADDITIVES

Abstract

Although enthusiasm for the use of cyclodextrins as enabling additives has gone through various phases, the advent of newer cyclodextrin derivatives with better safety records, has resulted in renewed interest of late. Generally, cyclodextrins (COs) are able to form inclusion complexes with numerous substances whose properties are of interest to various scientifiC and technological fields including pharmacy. Such inclusion of a guest molecule, in a molecule of cyclodextrin, is capable of changing considerably the physicochemical and even biological properties of the guest molecule. The advantages of the potential uses of COs, their availability, and economic reasons, play a decisive role in the growing interest in COs shown by the pharmaceutical industry.

Alternatively, other additives have significant effects on the dissolution characteristics of many drugs and so their bioavailability. Those additives comprise mainly hydrophilic carriers such as water-soluble polymers, sugars, organic acids and others.

Also, the effective surface area of hydrophobic drug particles can often be increased by the addition of a surface active agent to the formulation. This later functions by reducing the contact angle permitting thus more intimate contact between drug and surrounding aqueous medium during dissolution. As a consequence, drug dissolution rate could be enhanced.

The major aim of the present study is to investigate how far inclusion complexation with modified COs would affect inherent characteristics of poorly water-soluble drugs, in comparison with selected hydrophilic carriers and surfactants. The drugs which will be studied include two model drugs from two different pharmacological groups, suffering from problems in their biological performance.