Nonoral routes of administration

Table 46.10. Contraceptive Methods Using Nonoral Routes of Administration Estrogen Progestin ...

The use of food additive petitions and GRAS procedures to evaluate the safety of a proposed new excipient would apply to the oral route of administration for the excipient and would not generally apply to other routes of administration. Some routes of administration (e.g., inhalation) result in unique toxicological requirements, and data would have to be developed for the specific route of administration. While toxicological data from systemic studies are important for excipients used for nonoral applications, separate data would be needed for the specific route of administration. Nevertheless, the amount of safety data, specifications, and intake information required for a food additive review is extensive, and therefore could provide a firm basis of safety for a new excipient. 

The lack of activity after oral administration for most peptides and proteins resulted in the past besides parenteral application into the utilization of nonoral administration pathways, for example, nasal, buccal, rectal, vaginal, percutaneous, ocular, or pulmonary drug delivery [27]. Drug delivery via these administration routes, however, is also frequently accompanied by presystemic degradation processes. Bioavailability of numerous peptides and proteins is, for example, markedly reduced after subcutaneous or intramuscular administration compared to their intravenous administration. The pharma-cokinetically derived apparent absorption rate constant is thus the combination of absorption into the systemic circulation and presystemic degradation at the absorption... 

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