The mucus layers of the human gastrointestinal(GI) tract are mostly made up of mucin proteins, which are often divided into highly glycosylated and non-glycosylated mucin domains. There are two types of mucins: transmembrane mucins, which are present in the cell membrane and are mostly positioned on the apical side of epithelial cells, and gel-forming mucins released by mucus-producing cells. The GI tract's mucus layers protect the underlying epithelial surface from hazardous chemicals and pathogens by slowing pathogen diffusion to the epithelium. The mucus layer in the small intestine has a high concentration of antibacterial peptides and proteins, which eliminate germs that permeate through the top layers of the mucus layer. Mucus operates as a "barrier" that must be crossed in order to ensure effective oral medication delivery since, regrettably, this protective function also lessens the diffusion of medicines (lipophilic and hydrophilic) towards the epithelium. Mucoadhesion is described as the process by which interfacial forces hold two materials together for extended periods of time. If the materials are biological, the process is also known as bioadhesion. For decades, researchers have researched mucoadhesive materials, both natural and synthetic, and a few mucoadhesive drug delivery methods have been employed in FDA-approved medicines. Mucoadhesive drug delivery systems have extended stomach residence periods as a result of the interactions between the systems and the GI mucus components described above. These nanoscale or microscale medication delivery methods were primarily employed to provide tiny compounds orally. Although the subcutaneous approach eliminates the first-pass effect, it can result in peripheral hyperinsulinemia. Alternatively, oral insulin administration is the most convenient delivery method since it is inexpensive, safe, and painless. Oral insulin reaches the liver via the portal vein, lowering hyperinsulinemia and boosting cells' sensitivity to insulin, so using blood glucose more effectively. On the other hand, Oral drug delivery practices present significant challenges for the effective and efficient delivery of insulin. Poor intestinal absorption and enzymatic breakdown of high molecular weight hydrophilic macromolecules such as insulin reduce insulin bioavailability and hepatic metabolism. Therapeutic proteins like insulin experience serious threats by the enzymatic degradation within the GI tract. Chitosan, in this case, shields insulin from this enzymatic degradation, allowing the substantial amount of the active drug to reach the bloodstream. Hence, this mechanism is essential in the maintenance of the potency and bioavailability of insulin during its journey through the digestive system. Thus, the enzymatic protection provided by chitosan nanoparticles acts as a powerful advantage in utilization of oral intake of medicines. This was specifically studied by Pai et al., where the chitosan was applied to the lipid nanoparticles to enhance the physical stability. When applied to medications that are highly vulnerable to enzymes, such as insulin, the chitosan-lipid system can offer significant protection against enzymatic degradation.