> ## Content Index
> Fetch the complete content index at: https://www.fdaweb.com/llms.txt
> Use this file to discover other available public pages before exploring further.

# FDA Studies Nasal Spray Distribution
- URL: https://www.fdaweb.com/fda-studies-nasal-spray-distribution/
- Published: 2023-11-29T12:00:00.000Z
- Updated: 2026-09-14T14:17:15.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5155883

CDER researchers simulating how factors may affect corticosteroid nasal deposition say that on average, more than 94% of the medication went into the nasal cavity. “At least 91% of all drug mass entered the nose,” an online [post](https://www.fda.gov/drugs/news-events-human-drugs/computational-simulations-shed-light-factors-affecting-nasal-spray-distribution?ref=fdaweb.com) says. “Overall, the different sprays had little effect on medication distribution.”

The researchers examined three groups of factors — spray characteristics, human factors, and nasal anatomy — to better understand how they affect drug delivery for generic nasal drugs.

The post says the actuation force had a significant effect on how much medication reached the target site in the respiratory epithelium in the “healthy” computational model but not the “rhinitic” (inflamed) model. The airflow rate and nozzle depth followed the same pattern. FDA says the cone angle and nozzle subtraction did not produce a significant effect on either the healthy or rhinitic model.

“This study yielded several benefits for the development and approval of generic nasal drugs,” the report concludes. “Predictions suggested that human factors and nasal anatomy may explain much of the variability observed in human testing, which will help both industry and CDER when interpreting future *in vivo* data. Also, industry may choose to adopt the computational fluid dynamics method as an internal decision-making tool. Finally, the results helped CDER evaluate the clinical relevance of various spray characteristics. This may make generic drugs available faster by providing information on how similar these characteristics should be to demonstrate bioequivalence.”