ABSTRACT
Sterile dosage forms have always been an important class of pharmaceutical products in disease diagnosis, therapy, and nutrition. Certain pharmaceutical agents, particularly peptides, proteins, and many chemotherapeutic agents, can be administered only by injection (with or without a needle), because they are inactivated in the gastrointestinal tract when given by mouth. Administration of drugs by the parenteral (parenteral and injectable will be used interchangeably) route has skyrocketed over the past several years and will continue to do so. A primary explanation for this enormous growth lies with the advent of biotechnology, the products of which are biomolecules that cannot be readily administered by any other route because of bioavailability and stability reasons. Since human insulin became the first biotechnology drug approved by the Food and Drug Administration (FDA) in 1982, over 100 drug products of biotechnological origin have been approved and hundreds more will be approved in the years ahead. Most biotechnology drug products are administered only by the parenteral route. Science is advancing to a time when it is likely that some of these drugs can or will be administered by other routes, primarily pulmonary and perhaps someday even orally, but the mainstay route of administration for these biopharmaceutical drugs will be by injection.
