The fast-acting drug offers a new way to treat depression and fathom its origins. The recent approval of a nasal spray promises to expand access, but much remains unknown about long-term use and the potential for abuse.
At 32, Raquel Bennett was looking for a reason to live. She’d struggled with severe depression for more than a decade, trying multiple antidepressants and years of talk therapy. The treatment helped, but not enough to make it seem worth living with a debilitating mental illness, she says. “I was desperate.”
In 2002, following a friend’s suggestion, Bennett received an injection of ketamine, an anesthetic and psychedelic party drug also known as Special K. During her first ketamine trip, Bennett hallucinated that God inserted a giant golden key into her ear, turning on her brain. “It was as if I was living in a dark house and suddenly the lights came on,” she says. “Suddenly everything seemed illuminated.”
The drug lifted Bennett’s depression and dispelled her thoughts of suicide within minutes. The effect lasted for several months, and, she says, the respite saved her life. She was fascinated by the drug’s rapid effects and went on to earn a doctoral degree in psychology, writing her dissertation about Ketamine for sale. Today, she works at a clinic in Berkeley, California, that specializes in using ketamine to treat depression. “This medicine works differently and better than any other medication I’ve tried,” she says.
When Bennett experimented with ketamine, the notion of using a psychedelic rave drug for depression was still decidedly fringe. Since the first clinical trials in the early 2000s, however, dozens of studies have shown that a low dose of ketamine delivered via IV can relieve the symptoms of depression, including thoughts of suicide, within hours.
Even a low dose can have intense side effects, such as the sensation of being outside one’s body, vivid hallucinations, confusion, and nausea. The antidepressant effects of ketamine typically don’t last more than a week or two. But the drug appears to work where no others have — in the roughly 30 percent of people with major depression who, like Bennett, don’t respond to other treatments. It also works fast, a major advantage for suicidal patients who can’t wait weeks for traditional antidepressants to kick in.
“When you prescribe Prozac, you have to convince people that it’s worth taking a medication for several weeks,” says John Krystal, a psychiatrist and neuroscientist at Yale University in New Haven, Connecticut. “With ketamine, patients may feel better that day, or by the next morning.”
The buzz around ketamine can drown out just how little is known about the drug. In the April 2017 JAMA Psychiatry, the American Psychiatric Association published an analysis of the evidence for ketamine treatment noting that there are few published data on the safety of repeated use, although studies of ketamine abusers — who typically use much higher doses — show that the drug can cause memory loss and bladder damage. Most clinical trials of the low dose used for depression have looked at only a single dose, following up on patients for just a week or two, so scientists don’t know if it’s safe to take the drug repeatedly over long periods. But that’s exactly what might be necessary to keep depression at bay.
The analysis also warned about ketamine’s well-established potential for abuse. Used recreationally, large doses of the drug are known to be addictive — there’s some evidence that ketamine can bind to opioid receptors, raising alarms that even low doses could lead to dependence.
Bennett has now been receiving regular ketamine injections for 17 years, with few negative side effects, she says. She doesn’t consider herself addicted to ketamine because she feels no desire to take it between scheduled appointments. But she does feel dependent on the drug, in the same way that a person with high blood pressure takes medication for hypertension, she says.