The sedative midazolam is usually used before colonoscopies or dental surgeries. It puts you to sleep before you go under the knife — and induces amnesia so you don’t remember it.

But in recent years, the drug has been used as part of a cocktail of drugs used in carrying out executions for death row inmates around the country.

We spoke with the man who helped invent this drug and it turns out, he’s retired in Tucson.

Armin Walser is a Swiss chemist who worked for the pharmaceutical company Hoffmann-La Roche throughout his long career. And we tracked him down at his home in Tucson.

He says he’s been contacted by a lot of reporters recently, as the drug he invented in the 1970s has become central to the debate surrounding capital punishment in this country.

“No, I was not happy. I only learned about this two years ago," he said. "I’m not for the death penalty.”

It all started as he searched for an injectable replacement for valium. He says they finally came across the right combination in 1973.

“In 1984, it was approved by the FDA as a water-soluble injectable sedative. When they got to clinical trials, they found some changes they liked. It’s shorter acting than valium, it was immediately active, and it didn’t have to undergo a biotransformation first and that it had amnesic properties.”

And this went onto become a very successful drug. It’s used in hospitals and clinics around the country to patients who are about to undergo anesthesia. 

So what did he think when he realized that his life’s work was being used to help kill people on death row?

As you might expect, he was uncomfortable with the idea.

“I read about this, surprised, but going back to history of midazolam, there were cases where midazolam did not do the job. In my opinion, the interaction of midazolam with the receptor may not be effective in all people. I had a friend who said it wouldn’t work for him at all," he said.

And the question of whether this drug causes prisoners an unconstitutionally painful death is one of the major points that’s debated here.

The Supreme Court upheld the use of midazolam in a case from Oklahoma in 2015. But one of the most notorious cases happened here in Arizona in 2014, when Joseph Wood was executed using midazolam to put him to sleep and a narcotic. The combination was meant to be lethal but he didn’t die right away. Wood gasped and snorted in the execution chamber for nearly 2 hours before he died, and he was injected 15 times.

Walser says he doesn’t know what happened in this case, but he believes there are individual sensitivities to the drug he helped create.

“It’s not 100 percent effective in all people, 99 or 98 percent,” he said.

And the Wood case has led to lawsuits in our state over how the state carried out executions. This all also has to do with the larger debate around what states can do as execution drugs become more and more difficult to obtain.

In fact, Roche, the company that Walser used to work for, said in 2015 that it did not supply midazolam for use in the death penalty and wouldn't, according to The New York Times.

Arizona’s Department of Corrections has now agreed that it won’t use midazolam as part of lethal injections, but all of this has left Walser, who has never supported the death penalty, in a difficult position.

After all, midazolam is one of his career highlights, and, it’s part of his legacy.

“Very few medicinal chemists ever have a drug that’s marketable. I’m one of the few that was lucky enough to find a marketable product. I’m proud that I made it and that it helped many people, and it’s unfortunate they thought it was best for capital punishment.”