Our majority is not qualified to make medical decisions. That has been proven time and again. This is frightening.

Water, nitrogen, either way no oxygen, but a conscious death over (checking the records) some 20 minutes.
A firing squad is faster.

An overdose of morphine will do it with less drama.

If you absolutely have to execute folks, just get some of the fentanyl that is killing over 100,000 Americans a year.

It sems like a pretty efficient killing method, and I reckon it would be relatively painless.