Drug delivery is the method or process of administering a pharmaceutical compound to achieve a therapeutic effect in humans or animals[1] [2]. Drug Delivery technologies are patent protected formulation technologies that modifies drug release profile, absorption, distribution and elimination for the benefit of improving product efficacy & safety and patient convenience & compliance[3]. Most common methods of delivery include the preferred non-invasive peroral (through the mouth), topical (skin), transmucosal (nasal, buccal/sublingual, vaginal, ocular and rectal) and inhalation routes [4][5]. Many medications such as peptide and protein, antibody, vaccine and gene based drugs, in general may not be delivered using these routes because they might be susceptible to enzymatic degradation or can not be absorbed into the systemic circulation efficiently due to molecular size and charge issues to be therapeutically effective. For this reason many protein and peptide drugs have to be delivered by injection. For example, many immunizations are based on the delivery of protein drugs and are often done by injection.

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Drug delivery is a term that refers to the delivery of a pharmaceutical compound to humans or animals. Most common methods of delivery include the preferred non-invasive oral (through the mouth), nasal, pneumonial (inhalation), and rectal routes. Many medications, however, can not be delivered using these routes because they might be susceptible to degradation or are not incorporated efficiently. For this reason many protein and peptide drugs have to be delivered by injection. For example, many immunizations are based on the delivery of protein drugs and are often done by injection.

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The use of physical, chemical, and biological components to deliver controlled amounts of a therapeutic agent.

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Drug delivery, generally, describes the art of applying a therapeutic agent.

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