When the drug is administered into a body, it must reach the desired location to be effective. Due to the small quantity of the drug substance, it cannot be administered directly into the system, as it is quite difficult for such a small dose to reach the intended location. Therefore, a system or formulation is required to deliver the drug to the target site in the body.
A drug delivery system is a formulation or device that facilitates the delivery of drug substances into the body. The proper formulation is crucial for improving the safety and efficacy of the drug. The right drug delivery system efficiently controls the timing, location, and rate of drug release in the body to produce the desired drug effect. Common type of drug delivery route includes oral and parenteral methods, while delivery vehicle such as liposomes, dendrimers, nanoparticles, micelles, lipid crystals, and others are often used.