O ciekawe dlaczego prasa tego nie nagłaśnia, tylko szkodliwość USG :)




http://www.nature.com/news/2006/060807/full/060807-1
.html

The 'club drug' ketamine may be the fastest-acting antidepressant ever
tested, researchers report today.

A team based at the US National Institute of Mental Health (NIMH) in
Bethesda, Maryland, studied ketamine in 17 people with major depression. All
the subjects had failed to respond to treatment with standard antidepressant
drugs or more drastic methods, such as electroshock therapy. But 71% felt
better the day after taking ketamine, and 35% still felt better a week
later. None improved when dosed with a placebo.

Most striking, the scientists say, was that some patients felt better less
than 2 hours after taking ketamine. Currently approved drugs can take weeks
to remedy depression. The work is published in the Archives of General
Psychiatry1.

"It's almost like there's a sound barrier for those us who do depression
research, and we have not been able to break it," says Carlos Zarate, chief
of the mood and anxiety disorders research unit at the NIMH, and first
author of the study. "That's the exciting part of this - now there is
evidence that we can."

Zarate and his colleagues are not advocating that doctors start giving
depressed patients ketamine right away. Large doses of the drug can cause
brain damage in rodents, and its long-term health effects have not been
studied in people.

"We don't want to give anyone the message to run out on the street and use
ketamine," says Nuri Farber, a psychiatrist at Washington University in St
Louis, who was not involved with the work. "It makes you crazy - that's why
it's a banned drug."

Cure-all

Scientists are currently testing a wide range of recreationally
used-and-abused drugs, including ecstasy (MDMA; see 'The ups and downs of
ecstasy') and psilocybin, the active ingredient of magic mushrooms, as
potential therapeutics.

Ketamine, invented in 1962 as an anaesthetic, is chemically related to
phencyclidine (PCP), also known as angel dust. Both induce hallucinations
and out-of-body experiences, hence their use as illegal psychedelics.

Ketamine has milder psychotic effects than PCP and is therefore also used as
a legal anesthetic and horse tranquillizer. Scientists are studying whether
it can be used to treat alcoholism and chronic pain, as well as depression2.

Short-cut

Ketamine targets a brain protein called the N-methyl-D-aspartate (NMDA)
receptor. Existing antidepressants target brain chemicals such as serotonin,
but there is growing evidence that these drugs eventually affect NMDA
receptors. Ketamine may work so quickly because it takes a short-cut
straight to this part of the brain.

The psychotic effects of ketamine, such as euphoria, wore off before the
antidepressant effects kicked in, Zarate's team found, suggesting that the
drug's psychotic and antidepressant effects are separate. One surprising
aspect is that other drugs that induce euphoria, such as cocaine, usually
lead to a depressive crash once the high wears off.

Zarate's group is looking for substances with some of the chemical
properties of ketamine, such as the ability to target NMDA, without the
psychedelic effects.

Other scientists, including Farber, have developed drugs that can be taken
with ketamine to damp its side effects. Giving these drugs together might
help patients feel better without getting high.