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Updated: Feb 16, 2026

Novel Methods for Intranasal Administration Under Inhalation Anesthesia to Evaluate Nose-to-Brain Drug Delivery
Published on: November 14, 2018
Toxicology Evaluation of Drugs Administered via Uncommon Routes: Intranasal, Intraocular, Intrathecal/Intraspinal,
Armaghan Emami1, Jeff Tepper2, Brian Short3
11 US Food and Drug Administration, Silver Spring, MD, USA.
Abstract:
As the need for nasal, ocular, spinal, and articular therapeutic compounds increases, toxicology assessments of drugs administered via these routes play an important role in human safety. This symposium outlined the local and systemic evaluation to support safety during the development of these drugs in nonclinical models with some case studies. Discussions included selection of appropriate species for the intended route; conducting nonclinical studies that closely mimic the intended use with adequate duration; functional assessment, if deemed necessary; evaluation of local tissues with special histological staining procedure; and evaluations of safety margins based on local and systemic toxicity.
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