According to Collins English dictionary, drug deliverysystem is a system that is used as a medium or carrier for administering apharmaceutical product to patient (1) which consist of a formula of therapeuticsubstance and control time, rate and destination of the released drugs in thebody to enable and improve the efficacy and safety of the medicine. To developa new substance of drug is considered expensive and took a lot of time. So manyresearcher had attempt to study and developed the existing methode of deliverysuch as sustain released and delayed release. The term pharmaceutical material alsoapplies to an agent such as gene therapy that will induce in vivo production ofthe active therapeutic compound. Gene therapy can fit in the basic and broaddefinition of a drug delivery system.
Gene vectors may need to be introducedinto the human body by new delivery methods. Drug can be delivered through manyways e.g.
through mouth, skin (topical), and inhalation routes etc. It mayinclude a target area in the body concerned with quantity and duration of drugpresence. As rate and amount of dosage in the bodymust be well calculated so in the traditional drug delivery methods where doserate is calculated and delivered manually any type of mishandling can lead tocertain complications in a patient. This distinction between the drug and thedevice is important, as it is the criterion for regulatory control of thedelivery system by the drug control agency. Many investigation on human and animal have resultsthe increased understanding on the principles of pharmacokinetics andpharmacodynamics and influence the hypnotic, sedatrive and analgesic action andtendency. The research proves that there are another option for anesthetic andanalgesic drug route such as via buccal, skin, and nasal mucus.
This stimulatethe interest of pharmaceutical company to invest more research and developmentfind the new method of drug delivery system instead of looking for new pharmaceuticalsubstance. Because the cost of finding of new pharmaceutical substance from theresearch, develop, do the clinical test and for regulatory approval fromgovernment in the US is about $120 million and spent more than a decade. Butfor a development of improved drug delivery system cost roughly 40% of marketeddrugs at the US in 2000(2-4)