Table 3.

Investigations of intranasal systemic delivery.

API	Delivery System	Refs.
Morphine	Microparticles	[37]
Fentanyl	Spray	[38]
Buprenorphine hydrochloride	Solution	[39,40,41]
Ketamine	Solution	[42,43]
Sumatriptan	Gel in situ	[44]
	Nanoemulsion	[45]
	Powder	[46,47]
Zolmitriptan	Gel in situ	[48]
	Nanoparticles	[49]