April 3, 2014
Street Drug Shows Promise In Treating Depression
Brett Smith for redOrbit.com - Your Universe Online
Once considered an illicit street drug, marijuana is currently being seen in a new light – with many patients and doctors touting the benefits of regular cannabis treatments.
Another current street drug, ketamine, is now being looked at for its therapeutic value as a new study from UK researchers at Oxford University has found that relatively small doses of the drug are effective in treating depression.
According to the team’s report in the Journal of Psychopharmacology, regular intravenous injections of ketamine were able to bring relief to patients suffering from severe depression who had not responded to treatment via antidepressants or other measures. The dose used in the study was no more than 80 mg, compared to the several grams a day typically used on the street.
“Ketamine is a promising new antidepressant which works in a different way to existing antidepressants. We wanted to see whether it would be safe if given repeatedly, and whether it would be practical in (a hospital) setting,” explained study author Dr. Rupert McShane, a psychiatrist at Oxford University. “We especially wanted to check that repeated infusions didn't cause cognitive problems.”
To reach their conclusion, the Oxford scientists administered ketamine to 28 patients with treatment-resistant depression over the course of three weeks. Each treatment session involved three or six ketamine infusions lasting 40 minutes, all of which were all conducted in a hospital setting. Follow-up cognitive tests were conducted a few days after the final treatment session. Patients were asked to report their mood symptoms daily using text message or email.
While many participants relapsed within a couple days, the study team found 29 percent of participants in the study experienced a benefit which lasted at least three weeks and 15 percent went two months before relapsing into symptoms of depression.
Many ketamine abusers report severe bladder problems and cognitive impairment related to their drug use. However, the researchers did not find evidence of these side effects in their trials – perhaps because such a low dose was used.
“We've seen remarkable changes in people who've had severe depression for many years that no other treatment has touched,” McShane said. “It's very moving to witness. Patients often comment that that the flow of their thinking seems suddenly freer. For some, even a brief experience of response helps them to realize that they can get better and this gives hope.”
While bladder and cognitive issues did not arise, some participants became anxious during the intravenous infusions and some did not finish the course simply because they did not feel they were reaping any benefits. A few volunteers were sick and one fainted. Some of the severely depressed participants did go through episodes of suicidal behavior. However, these episodes had happened before the treatment. Overall, suicidal thoughts diminished during the study, the researchers said.
“Intravenous ketamine is an inexpensive drug which has a dramatic, but often short-term, effect in some patients whose lives are blighted by chronic severe depression,” McShane said. “We now need to build up clinical experience with ketamine in a small number of carefully monitored patients. By trying different infusion regimes and adding other licensed drugs, we hope to find simple ways to prolong its dramatic effect.”