JOHN YANG: A coroner's determination that actor Matthew Perry died from the acute effects of ketamine is drawing new attention to the drug.

It's a powerful anesthetic intended for use during surgery.

But it's also become a popular treatment for some mental health problems.

And because of its psychedelic effects, it's also used recreationally.

Perry's autopsy reports as the 54-year-old actor was on ketamine therapy, but that the level in his system was too high to have come from his last known therapy session.

According to a healthcare analytics firm since 2017, ketamine prescriptions have shot up 500 percent for profit clinics and telehealth services prescribe it for chronic pain, depression, anxiety, and other conditions, none of which are approved by the Food and Drug Administration.

Medical professionals warn there's limited research into the effects of long term ketamine use.

Dr. Caleb Alexander is a professor of epidemiology and medicine at the Johns Hopkins Bloomberg School of Public Health.

Dr. Alexander, thanks for being with us.

First of all, just tell us what does ketamine do and why would it be preferable in surgery over something else?

DR. CALEB ALEXANDER, Johns Hopkins Bloomberg School of Public Health: Well, ketamine is a very rapidly acting anesthetic, and it was developed in the 1960s to treat people with battlefield trauma and in highly supervised clinical settings, like an operating room.

And so in this instance, it was well studied and the Food and Drug Administration approved it, believing I think, rightly that it was safe and effective in these settings.

JOHN YANG: Patients who were prescribed this by clinics and telehealth operations who use it long term or chronically.

Are they reporting having disturbing side effects?

CALEB ALEXANDER: Yeah, well, it's important to emphasize that the safety and effectiveness of a drug isn't a static feature of the drug any more so than we would say that a hammer or a roll of duct tape is good or bad.

But what we're seeing with these clinics is that ketamine is being used not for treating someone that's having their appendix taken out.

It's being used to manage depression, anxiety, post-traumatic stress disorder, chronic non-cancer pain.

And so it's being used in ways that are vastly different than the ways in which it's been studied by the U.S. Food and Drug Administration.

JOHN YANG: And what are the risks of that?

CALEB ALEXANDER: Well, I think there are huge risks.

I mean, when we think about whether or not a drug should be used, it's not just about benefits.

And it's not just about safety.

It's about the balance of benefits and safety.

And in the case of ketamine, for these sorts of uses for anxiety or for post-traumatic stress disorder, not only do we not know very much about whether it's effective.

There are also real risks, risks, including neuro psychiatric effects, that can be long term, cardiovascular effects, changes in blood pressure and in the body circulation, and bladder effects in inflammation of the lining of the bladder to name just a few.

JOHN YANG: Why do you think it's become so popular among clinics and telehealth providers to prescribe it?

Why are their prescriptions shot up so much?

CALEB ALEXANDER: Well, it's a very good question.

One factor I think is simply greed.

It's the profit motive of the clinics and the telehealth companies that can stand to gain tens of thousands millions of dollars through it sale.

We also have seen in a surge of interest in the use of psychedelics things such as psilocybin, which is derived from mushrooms, and a surge of interest in the use of psychedelics for the treatment of psychiatric illness.

I think both of these are factors that may be contributing.

JOHN YANG: And as this is also prescribed for chronic pain?

CALEB ALEXANDER: It is.

It is.

And it's worth noting, unfortunately, we're still in the midst of an opioid epidemic.

And we've lost far too many lives from opioids.

And I think we've learned the hard way that in most instances that prescription opioids are not great medicines for the management of chronic non cancer pain.

And this too, may be driving some interest and in the use of ketamine, but I certainly wouldn't say that we have more evidence for ketamine than opioids for these instances.

JOHN YANG: Now explain to us the, I guess it's a loophole and regulation that allows a doctor who never sees the patient in person who does it by Zoom, to prescribe a psychedelic to somebody in that way.

CALEB ALEXANDER: The bottom line is that there is an important loophole in our system of regulating how prescription drugs can be marketed.

And this loophole needs to be closed.

We have a patchwork of regulations by the Federal Trade Commission, the U.S. Food and Drug Administration and consumer protection laws.

And these restrict how pharmaceutical companies the makers of ketamine can market and promote the drug, but they don't necessarily restrict how other companies, these telehealth companies and freestanding clinics can market and promote the drug.

The bottom line is that our regulations governing drug promotion were conceived and were written in an era before these companies existed.

And so we now have companies that are exploiting these loopholes, and marketing this drug making wildly outlandish claims about it safety and effectiveness.

JOHN YANG: Someone who has chronic pain, someone who's suffering from depression or anxiety hears these claims.

What would you want them to know and think about before they go to their doctor and say, Hey, how about trying this?

CALEB ALEXANDER: One of the most important lessons that I think we've learned from the opioid epidemic is that we have many tools in the toolbox.

We have many tools in the toolbox to manage chronic pain.

And we also have many tools in the toolbox to manage depression and other psychiatric illness.

And I think it's vital that we keep in mind that we do have options.

I'm talking about both pharmacologic options, prescription drugs, and also non pharmacologic options.

So I think both of these are important to keep in mind.

JOHN YANG: Dr. Caleb Alexander from the Johns Hopkins Bloomberg School of Public Health Thank you very much.

CALEB ALEXANDER: Thank you for having me.