Preparation of new topical formulations containing etodolac and in vitro characterization studies.

Non-steroidal anti-inflammatory (NSAID) drugs are frequently preferred in acute and chronic musculoskeletal diseases such as rheumatoid arthritis, osteoarthritis, tendonitis, sprains and strains. When systemic effects are targeted using the oral route, NSAIDs are known to cause serious gastrointestinal side effects such as dyspepsia and stomach bleeding. Etodolac is a BCS class II NSAID drug with low solubility and high permeability properties. As with other NSAIDs, the most common side effect of etodolac is on the gastrointestinal system. There are pharmaceutical preparations in the form of topical gels, creams and ointments that eliminate the systemic side effects of NSAIDs and provide local effects. The stratum corneum is the most important barrier in terms of accumulation of topically applied drugs in the target area of the skin. In topically applied dosage forms, it is desired that the molecule first be released from the formulation and diffuse into the stratum corneum layer of the skin and then reach the epidermis. Topical dosage forms determine the dermal and transdermal delivery and therapeutic efficacy of the active substance by the type of formulation used and its basic composition. This therapeutic aspect changes with the basic composition and physicochemical properties of the formulation. Emulsions are biphasic semi-solid systems obtained by gelling oil-in-water or water-in-oil emulsions using a gel forming agent, depending on the intended use. The fact that emulsions have both emulsion and gel properties enables these systems to exhibit double-controlled release properties. It has advantages such as dissolution of both hydrophilic and hydrophobic drugs and good thermodynamic stability. Therefore, when it is desired to prepare topical formulations of etodolac, which has a very low water solubility, emulsion formulations will provide an important advantage. The purpose of this thesis is; To improve the topical application emulsion formulations of etodolac, which is a molecule with suitable properties due to its physicochemical and pharmacological properties, to reduce side effects and increase patient compliance, and to evaluate in vitro characterization of emulsion formulations prepared using different penetration enhancing substances.