Ketamine is being used to treat depression in clinics that are springing up across the United States, but uncertainty remains over its long-term use.
It rains for 164 days out of each year in Portland, Oregon, a city renowned for its wet weather. So it seems an unlikely destination for patients hoping to alleviate their depression. Yet, over the past two years, almost a hundred people have visited a small nondescript clinic in this damp corner of Northwestern United States to receive ketamine, an experimental treatment for depression that can work where other drugs have failed.
Ketamine has been used as anaesthesia during short operations and pain relief during minor procedures for the past 40 years. Like a number of the other doctors offering ketamine for depression, Abreu is an anesthesiologist experienced in administering ketamine in the operating theatre. He prefers to closely guard the location of the clinic he opened in 2013 for fear that thieves will target his stock of ketamine, which can be sold on the nightclub scene.
Abreu is not alone in his caution. Only 18 clinics are publically listed on the Ketamine powder for sale Advocacy Network, a website that provides a platform for discussing ketamine’s use in depression, but the real number of clinics that have sprung up across the United States is likely to be closer to 60. “There are at least three times as many clinics doing it but not publicising it,” says Abreu. When he started his clinic he didn’t advertise for a year. This was also because he was scared of the reaction. “I didn’t want the community to think oh, this is just some quack job, there is this stigma and it is hard to get around.”
In the 1990s, it became apparent that the dissociative effects of ketamine had made it popular on the clubbing scenes of Europe and Asia. Estimates put population use of ketamine at 1% in Denmark and 0.5% in Thailand.
At the moment, ketamine is not subject to international controls, which are designed to limit the abuse of recreational drugs. But China has now placed a proposal before the United Nations Commission on Narcotic Drugs to have ketamine placed in schedule 1 of the Convention on Psychotropic Substances of 1971. This would put ketamine under the tightest possible international restrictions — usually only reserved for drugs with a very narrow medical application and high abuse potential. The World Health Organization (WHO) is opposing the move, saying that it does not believe the threat to public health is significant enough to warrant international controls. It says scheduling would limit access to ketamine in poor countries where it is a vital anaesthetic with a wide safety margin, and the restrictions would also make research in Western countries more difficult.
In the United States and Canada, more and more doctors are quietly beginning to prescribe the licensed anaesthetic off-label to patients. In 2006, results from the first randomised controlled trial (RCT) of ketamine for treatment-resistant depression suggested it can reverse major depression in as little as an hour— when more conventional pharmaceuticals can take weeks to start working, if at all. “These people come to me at their wits end and by their third or fourth infusion of ketamine they’re like a different person,” says Enrique Abreu, medical director of the Portland Ketamine Clinic. “I have not seen any other medicine that has such a profound effect in such a short space of time.”