FlyNap is nitrous oxide for fruit flies.

Genetic experiments performed on the common fruit fly have yielded some of the most important discoveries in biology. But when you need to study them, how do you get the damned little things to stay still?

Answer: you give them a mild dose of FlyNap, a solution of triethyamine in ethanol sold by the Carolina Biological Supply Company. The stuff comes in a little bottle with a dropper or a swab; you place just a few drops on a piece of cotton or on a q-tip and leave it in the fly chamber. In a few minutes the drosophilae are off in dream land . . .

While they sleep you're free to do any sort of screening or phenotyping you want. The flies will stay down for 5-30 minutes depending on how much you give them and for how long — and, yes, if you give them too much they tend not to wake up. Otherwise, FlyNap is harmless to them.

Is FlyNap bad for humans? Well, according to the MSDS sheet, yes:

Triethylamine is a severe irritant to eyes and mucous membranes.
Prolonged overexposure to triethylamine may cause damage to liver
and/or kidneys.
Emergency Overview:
Potential Health Effects:
Eyes: May cause irritation.
Skin: May cause irritation.
Ingestion: May cause gastrointestinal discomfort.
Inhalation: May cause irritation to respiratory tract.

And according to my own personal experience, yes. If you get this stuff on your skin it takes about 24 hours to get it off, even after repeated washings with acetone. If you should be so unfortunate as to get this stuff somewhere close to your mouth or nostrils then you will be smelling the stuff all day. It does get you a bit high, but its also nauseating.*

*No, for the love of God I was not so desperate that I turned to huffing FlyNap. What happened was this: After getting the stuff on my fingers, I went to play trombone for about an hour. Playing the 'bone requires that you keep your left hand close to your nose and mouth all the time — and you can guess what happened: I spent the entire hour inhaling the fumes coming off of my fingers, and by the time I realized what was happening I was right wacky.