COVINGTON, La. — Ketamine has been successfully used for decades for anesthesia. Today, called Special K, it is illegal as a schedule III controlled substance because of its additional use as a common date rape drug. 

As a result, it became controversial when some doctors started using ketamine for an unapproved use, known as 'off-label,' to treat depression and pain.

Now, there is a newly-approved nasal spray version of the drug.

In the fall of 2017, Eyewitness News showed patients suffering with excruciating physical pain or suicidal depression. They had turned to Dr. Brian Ball in Covington for help. 

Ball was the only doctor in Louisiana using the surgical anesthesia drug for these conditions. It's a drug he said he's used in the operating room for decades as an anesthesiologist. His patients said the IV treatment was life saving.

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"I love him. I call him my miracle worker. He's given me back my life," said a patient in 2017.

Back then, other physicians were skeptical, saying they needed more human studies to assure that it works and is safe without long-term side effects on the brain. 

Just recently, the FDA approved a version of ketamine, called esketamine, to treat severe depression. Soon the nasal spray will be offered only at specialty pharmacies. It will be legal to use while the patient is with a physician in his or her office.

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Esketamine, however, is only a fraction as effective as the IV drips used at the Ketamine Infusion Center in Covington, according to Ball.

"[Ketamine infusion] is about a tenth of the cost of esketamine, but we're not paid for. It's not covered by insurance, but we have an 80 percent or greater response rate [to the IV,] Ball said. "Esketamine is about a 30 percent response rate."

Ball said he has gotten such strong results with the IV version, that he is now planning to open another office in Metairie.

"We pretty much cure fibromyalgia, treatment-resistant migraine, any sort of neuropathy. Pretty much cure it, whether it's from diabetes, trauma, you name it," Ball said.

There are currently no medically-accepted cures for fibromyalgia or diabetes.

Bell said his center has a high success rate with suicidal patients. He believes the FDA approval of esketamine brings awareness to a drug that can help people who have tried everything else. However, he doesn't want patients to give up IV treatment if the new nasal spray is less effective.

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"The benefit of ketamine treatment is truly from getting a blood level and maintaining it for optimal period of time. That's why IV ketamine is still the gold standard," Ball said.

Reported side effects of ketamine treatments can include nausea, vomiting, raised blood pressure, and delirium, Ball said.