The use of naturally occurring biocompatible materials has been the focus of recent research activity in the design of dosage forms for immediate and controlled release formulations. Grewia gum is an intracellular gum obtained by extraction from the inner stem bark of the shrub Grewia mollis (Malvaceae). It grows abundantly (wild or cultivated) in the middle belt region of Nigeria, and the mucilage has been used by indigenes of this belt as thickener in soups. Grewia gum has been investigated for potential applications in pharmaceutical dosage forms. The industrial extrapolation of the applications of the gum has, however, been slowed by the limited structural, toxicological, and stability data available on the gum. This paper highlights ethnobotanical uses of G. mollis shrub and discusses the structural features, functional properties, and applications of grewia gum with emphases on its pharmaceutical potentials. 1. Introduction Plant materials are playing increasing role as alternatives to chemical food additives and synthetic pharmaceutical excipients. Natural polysaccharide gums swell to form highly viscous solutions or dispersions in aqueous media. They have the advantage of biocompatibility, low cost, and relative abundance [1] compared to their synthetic counterparts. They are widely used in the pharmaceutical industry as polymers in various drug delivery systems [2–7]. Grewia polysaccharide gum is a natural resource that could be used as an excipient in the pharmaceutical industry in Nigeria to reduce the costs of pharmaceutical products. It may provide a suitable alternative to the synthetic counterparts which are expensive and mostly imported. It is obtained by extraction (maceration in cold or hot water) of the inner stem bark of the edible plant G. mollis, Juss (Malvaceae). In Nigeria, G. mollis from which the gum is extracted grows abundantly (wild or cultivated) in the middle belt region of the country where it is used as thickener in local delicacies. This review delineates the ethnobotanical uses, physicochemical properties, structural properties, and the potential applications of the gum in drug delivery systems. 2. Grewia mollis Plant G. mollis belongs to the flowering plant genus, Grewia. It was formerly placed in the family Tiliaceae or Sparrmanniaceae. Today most authors place the genus in the mallow family Malvaceae. 2.1. Botany The plant has been described [8, 9] as a shrub or small tree growing to attain a height of 10.5？m with young branches densely stellate-pubescent. The young branches turn dark grey to black or reddish brown
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