Depression is the most common mental illness in the U.S., affecting more than 16 million people. Approximately one in six Americans takes medication to treat depression and anxiety.

SSRIs (selective serotonin reupdake inhibitors), sold under brand names such as Zoloft, Lexapro, Paxil and Prozac, are the go-to medications to ease symptoms. While SSRIs work well for many people, they don’t work for everybody. Nearly 30 percent are either unable to tolerate SSRIs or respond poorly. SSRIs can also take up to six weeks to work. People with treatment-resistant depression can be left feeling hopeless when nothing seems to work.

Studies now show a promising and effective new treatment in a surprising source—the drug ketamine. Ketamine, or its street name “Special K,” has been around since the late 1960s. Its original use was as a rapid-acting anesthetic used to manage pain. Illicit use of the drug, known to create a dissociative, dream-like state, gained popularity in nightclubs during the onset of the rave scene in the late 1990s.

Despite the stigma, ketamine may become an important new treatment for treatment-resistant depression. The rapid response patients have to the drug is remarkable, notes Dr. Mark Gold, Chairman of RiverMend Health’s Scientific Advisory Board. Relief can happen immediately, even after the first dose. When given in small doses, ketamine can be ideal for treating those with chronic depression and suicidal thoughts, with positive effects lasting up to seven days.

“Primarily, ketamine has been used in anesthesiology for nearly 50 years. But recently, important research has shown that ketamine hydrochloride can rapidly change mood, reverse suicidal thinking, and produce persistent antidepressant effects in patients with persistent depression, mood and anxiety disorders.,” Dr. Gold says.

Ketamine’s use as an antidepressant is not FDA-approved. While some psychiatrists are using ketamine as an “off-label” treatment for depression and suicidal thoughts, the proper dosage and safe usage of ketamine is still being studied. If ketamine is misused it can cause immobility, amnesia and hallucinations and should not be used outside of a clinical setting and careful monitoring by physicians. The American Psychiatric Association recently issued a report on the growing usage of ketamine.

“Researchers, like me, view ketamine as a major advance in our understanding of the etiology of depression, primarily due to the nearly immediate effectiveness and short duration of ketamine,” Dr. Gold says. “These data suggests to me, and others, that we are on the verge of a new and novel understanding of depression and the development of a new class of antidepressant treatment. Ketamine unlocks a key in the brain that clearly provides immediate relief to some treatment resistant depression patients.”

Read how Bluff Plantation treats co-occurring disorders.