Potential Application of Non Aqueous Emulsion for Drug Delivery

Conventional emulsions are heterogeneous system in which one immiscible liquid is dispersed as droplets in another liquid. That may be water-in-oil or oil-in-water emulsions. However emulsion can be formulated waterless or without an aqueous phase to produce anhydrous or non-aqueous or oil-in-oil emulsions may be used as reservoirs to deliver lipophilic or hydrolytically unstable drugs, could be considered as depot formulations for sustained release drug delivery. Such systems, presence of water to be avoided. Some drugs are unstable or not soluble in water, formulation of such drug for oral administration has more difficult. Oral drug delivery vehicles must be capable of maintaining sufficient drug concentration in a bioavailable form that will enable expected absorption and biological activity. Such drug delivery vehicles must also be capable of maintaining the drug in its dissolved state and maintain stability of drug. This can be achieved by formulating the non aqueous emulsion. Most important factor considering formulation of stable anhydrous emulsion for oral delivery is concentration of surfactant. At high surfactant concentration may inhibit lipolysis and is disadvantageous to the intestinal mucous and has potential of causing local irritation side effects. So there is a need for such vehicle that will not comprise high and significant portion of surfactants that are irritating to the gastro intestinal mucous.