(NewsNation) — Tianeptine is marketed as a dietary supplement, a little something to help you relax. But it’s also highly addictive and in some cases, deadly.

Its street name is “gas station heroin” and it’s easy to get. It can be purchased online and, as its name suggests, at gas stations and in your neighborhood convenience stores.

Just because it’s easy to get doesn’t mean it’s safe to use. Among the ingredients in these so-called dietary supplements is tianeptine, a drug the U.S. Food and Drug Administration (FDA) warns is harmful and addictive.

Dr. Kirsten Smith, a researcher with the National Institute on Drug Abuse, said it is dangerous for people to be taking.

“So far there’s absolutely no understanding of the dosage,” Smith said. “And certainly, no, it’s not approved for any medical use. And it’s absolutely not approved as a dietary supplement. In fact, it’s actually on the FDA’s list of concerning substances.”

In powder or tablet form, tianeptine is used to treat depression in some European, Latin American and Asian countries.

But here in the U.S., tianeptine is unapproved for medical use.

But that’s not stopping people from using it.

Illegally marketed as a dietary supplement, products containing tianeptine are sold under names like Za Za Red, Pegasus, T-D Red and Tianna.

The capsules come in bright-colored bottles with advertising claiming it helps improve brain function, treats anxiety, depression, pain, and opioid use disorder.

According to the FDA, the claims are dangerous, unproven and the products are linked to hundreds of overdoses and deaths.

“Essentially, it’s deemed adulterated by FDA because it is not meeting the standards set forth under federal law as a dietary supplement,” Smith said. “So to that end, people are consuming a product that they actually don’t know what’s in it.”

NewsNation spoke to several users of tianeptine who did not want to go on camera.

This is what they said:

• “You have to dose every 4 hours to prevent withdrawal once you’re hooked….That’s 5 or 6 bottles a day…it’s easily a $150-a-day habit.”
• “I couldn’t believe how much it resembled opiates.“
• “The anxiety was excruciating getting off tia.”
• “I’ve taken 75 pegasus pills some days…this went on for 4 years.”
• “I used to have a 6-9 bottle a day habit.”

For roughly $30 and a trip to the local gas station, users who in many cases sought a way to wean themselves off opioids are instead finding a new high in an over-the-counter substance they bought for help.

It gives many users an opioid-like high when taken in high doses.

But users say the effects wear off after only a couple of hours, leaving them chasing the same euphoria by popping more and more pills.

Tianeptine addiction can be a vicious and costly circle.

Some tianeptine users admit spending up to $200 a day on the product.

One user NewsNation talked to said he spent $2,000 a month on the drug, sacrificing food for his family to buy more Za Za Red before finally quitting cold turkey.

His quitting resulted in extremely painful opioid-like withdrawal symptoms that he said lasted several days.

“Many people who do become addicted are experiencing what they describe as extremely painful opioid-like withdraws, Smith said. “They’re saying the tianeptine withdrawal is actually as bad as if not worse than some of the opioids they’ve tried.”

Some states have been promoted to crack down on these products.

So far, the drug is banned in Michigan, Alabama, Minnesota, Tennessee, Georgia, Indiana and Ohio. Just this week, Mississippi became the latest state to ban tianeptine

Mississippi deemed the drug a controlled substance with a fine for possession of up to 30 years in prison.

According to Consumer Reports, tianeptine-related calls to poison control centers have skyrocketed over the last few years.

There have been hundreds of calls over the last several years and nearly 900 since 2015.

This is up from just 27 the entire decade before and officials say the numbers are likely much higher because many drug overdoses go unreported.

The biggest problem the FDA admits is having no way of knowing what dietary supplements are on the market or what’s in them.

In a statement, the FDA said, in part, “The FDA is committed to doing everything within its resources and authorities to identify and remove unsafe and illegal dietary supplements from the market, however, the FDA currently has no systematic way of knowing what dietary supplements are on the market, when new products are introduced, or what they contain – even if they contain ingredients we have previously acted against.

This allows makers of these products to line vape and gas station store shelves with unregulated substances where they get into the hands of anyone young or old with $30.

If you need help treating an addiction to any of the products containing tianeptine or opioids, you can find licensed providers at www.Findtreatment.Gov. Or call 1-800-662-help.