I was given a few of these nicotine packets and I used them on my recent flight.
I used 2 of them in water, a few times ( long flights) and they worked very well.
Aqua-tine | Homeopathic Relief from Tabacco Cravings
I had a small cheap E-cig, if needed, to stealth vape.
The FDA regulates homeopathic differently than other products which is how I suspect
a nicotine product like this is sold.