The oral route of drug administration is still considered as most preferred and favorable route. However, this route of administration causes some problems related to drug solubility and deliverance of proteins and peptides. To overcome these issues different dosage forms were formulated and characterized to enhance oral bioavailability of lipophilic drugs. Techniques that include salt formation, liposomes, and complexation were employed but the Self-emulsifying drug delivery system (SEDDS) gained more importance as it is considered to improve the oral bioavailability of active pharmaceutical ingredients (API) that are insoluble in water. This dosage form formulates oil in water (O/W) emulsions as it gets diluted in the gastrointestinal tract (GIT). Agitation provided by GIT enables them to formulate emulsion upon dilution with GIT contents. Approximately 40% of the new APIs were lipophilic in nature which decreases their aqueous solubility and ultimately their bioavailability was decreased. Formulations prepared by SEDDS hence, improve solubility and bioavailability of drugs. Another use of SEDDS is that it can be used to bypass first-pass metabolism and proteins, and peptides can easily be delivered through the oral route.

Keywords: Bioavailability, First pass effect, SEDDS, lipophilic, drug delivery, Oral route