People who use it say it is a miracle drug, but the government says it might be dangerous.

We are talking about kratom, an herbal supplement that's seen a huge surge in popularity, including here in Tucson.

"I think that more people are definitely aware of it. More people are using it," said Steve Dudley, PharmD., with the Arizona Poison and Drug Information Center.

Kratom is an herbal supplement derived from a plant that grows in southeast Asia...

At lower doses, kratom is a stimulant. When the dose is increased, experts say the effects are much different.

"At higher doses, kratom does act just like an opioid does. It hits on the same receptors; causes the same issues. so you can see sedation, difficulty breathing," Dudley told the News 4 Tucson Investigators.

Since the News 4 Tucson Investigators first told you about kratom nearly two years ago, calls to the Arizona Drug and Poison Information Center have spiked, with some patients reporting increased heart rate, nausea, or vomiting after taking kratom - either alone, or in combination with other drugs.

"More users, you're going to have more calls. Someone is going to have an adverse effect," Dudley told the News 4 Tucson Investigators.

In 2016, calling kratom "an imminent hazard to public safety" the Drug Enforcement Administration planned to make it illegal. Ultimately, the ban was delayed. The following year, the Food and Drug Administration said there were 36 deaths associated with the use of kratom-containing products.

"Any foreign substance we put in our body can cause harm, at the right dose and under the right circumstances," Dudley told the News 4 Tucson Investigators.

For people who are in the business of selling kratom, any talk of a potential ban is troubling. They point to research on the supplement, showing it has beneficial effects, and maintain that scheduling of the supplement by the DEA is not warranted. They also argue that the FDA is failing to follow the science on kratom.

"Everyday is somewhat of a battle with the government, in terms of keeping kratom legal," said Jill Fickettt, who runs Miracle Koffee, a business in central Tucson that sells Kratom in powder and capsule form.

Fickett told the News 4 Tucson Investigators, her shop has countless satisfied repeat customers, and she does not sell the product to people under 18.

"They're here because they want to do something natural, and they want to better their lives," Fickett said.

Fickett also told the News 4 Tucson Investigators, she has found that kratom helps relieve chronic pain and more, without harmful side-effects.

"It helps with mood, depression, anxiety," Fickett said. "It's an all-natural alternative to an opiate," she added.

Ficket also told the News 4 Tucson Investigators, she believes there has been misinformation put out by kratom's opponents.

"That's the most important thing, is it does not suppress the respiratory system like opiates do," Fickett said.

Though, with an uncertain legal future, Fickett worries her customers might be left hurting, if the government were to outlaw kratom.

"There's not enough research on kratom. People don't know enough about it. I think that's why it's somewhat controversial." Fickett told the News 4 Tucson Investigators.

Click here for more information on kratom from the American Kratom Association.

If you have something you would like the News 4 Tucson Investigators to investigate, email us - at investigators@kvoa.com, or call the News 4 Tucson Investigators tip-line at (520) 955-4444.