| LONDON, April 3
LONDON, April 3 The party drug ketamine could
one day be used to help some people suffering from severe
depression, according to British scientists who gave infusions
of the narcotic nicknamed "special K" to patients.
Researchers who tested the drug on 28 people with major
depressive disorder found ketamine quickly helped relieve the
condition for some - and made a number of them completely well
again for up to several weeks.
"It's dramatic and it's exciting, and it is a novel
mechanism. But it's not about to become a routine treatment,"
Rupert McShane, a consultant psychiatrist and researcher at
Oxford University who led the study, told reporters.
He said the discovery that ketamine worked, even for a short
period, had been enough to give new hope to some of the patients
in the study - many of whom had in the past considered suicide.
"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."
Although many of them relapsed within a day or two, almost a
third of them felt a benefit which lasted at least three weeks,
he said, and 15 percent did not relapse for more than two
"We now need to build up clinical experience with ketamine
in a small number of carefully monitored patients," McShane
said. "By trying different infusion regimes and adding other
licensed drugs, we hope to find simple ways to prolong its
Ketamine is a licensed medical drug, widely used as an
anaesthetic and to relieve pain. But it is also used as a
recreational drug and can lead some people into drug abuse.
McShane said that the doses used were very different. On the
street, users often take several grams a day and can suffer
severe bladder problems and impaired brain function. The dose
used in the study was no more than 80 milligrams - 80
thousandths of a gram - every week in a closely monitored
Several research teams around the world have been studying
the potential for ketamine use in depression, since many
patients with the psychiatric condition fail to respond to
currently available antidepressants such as Prozac and Seroxat.
The U.S. drug giant Johnson & Johnson is developing
an intranasal form of the drug, called esketamine, in mid-stage
trials and has said its results so far have been promising.
Anglo-Swedish drugmaker AstraZeneca had also been
conducting early-stage trials on a ketamine-like drug, but opted
to discontinue its development after disappointing results.
In the Oxford study, 28 patients with severe and
treatment-resistant depression were treated over three weeks and
received either three or six ketamine infusions each lasting 40
Memory tests were carried out a few days after the final
infusion and patients reported their mood symptoms daily via
text or email.
The results, published in Journal of Psychopharmacology,
showed that three days after the last infusion, the depression
scores had halved in 29 percent of the patients.
Some patients described feeling able to think freely for the
first time in years, he said, adding: "For some, even a brief
experience of response helps them to realise they can get better
and this gives hope."
(Reporting by Kate Kelland; Editing by Andrew Heavens and Sonya