(CNN) The US Food and Drug Administration approved Janssen Pharmaceuticals Inc.'s esketamine on Tuesday for treatment-resistant depression; the drug is the chemical cousin of ketamine, the powerful anesthetic that has been used illegally as the club drug Special K.

It will be sold as Spravato. More specifically, it's for patients who have tried at least two other medications without success, and it should be taken with an oral antidepressant.

"There has been a longstanding need for additional effective treatments for treatment-resistant depression, a serious and life-threatening condition," Dr. Tiffany Farchione, acting director of the Division of Psychiatry Products at the FDA's Center for Drug Evaluation and Research, said in a news release announcing the approval.

Spravato is a nasal spray administered by an approved health care provider in a doctor's office or a medical clinic. It may also be self-administered but only under the supervision of a care provider and cannot be taken home.

"Because of [safety] concerns, the drug will only be available through a restricted distribution system and it must be administered in a certified medical office where the health care provider can monitor the patient," Farchione said.

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