Treatments for nausea and vomiting can include some oral medications, rectal suppositories, and IV combinations. Through compounding new routes of administration or combinations can be made, including transdermal and intranasal routes.
https://www.ncbi.nlm.nih.gov/pubmed?term=8625179
Intranasal metoclopramide.
https://www.ncbi.nlm.nih.gov/pubmed?term=10473023
Nasal absorption of ondansetron in rats: an alternative route of drug delivery.
https://www.ncbi.nlm.nih.gov/pubmed?term=10803929
Bioavailability of Promethazine in a Topical Pluronic Lecithin Organogel: A Pilot Study
https://www.ijpc.com/abstracts/abstract.cfm?ABS=2203