Routes of Exposure: Other

This chapter will review the unique aspects of safety-testing strategies for excipients intended for ophthalmic, vaginal, rectal, and other mucosal routes of exposure. One obvious concern with materials intended for direct contact with mucosal surfaces is the delicate nature of these surfaces and the need to avoid inducing local irritation. Another feature is the rapid absorption that usually occurs for materials applied to mucosal surfaces. The feature that is probably most critical to establishing testing strategies for these mucosal formulations is the limited volume of material that can be administered by the intended routes and the consequent difficulties in establishing reasonable multiples of human exposure for safety assessment.