DIR Return Create A Forum - Home
---------------------------------------------------------
confessionsofabpgirl
HTML https://confessionsofabpgirl.createaforum.com
---------------------------------------------------------
*****************************************************
DIR Return to: General Discussion
*****************************************************
#Post#: 23--------------------------------------------------
Experimental Medication Lifts Depression Symptoms in Bipolar
Disorder W/I HR
DIR By: Bipolar Girl
Date: August 31, 2010, 4:07 pm
---------------------------------------------------------
Science Update • August 06, 2010
Experimental Medication Lifts Depression Symptoms in Bipolar
Disorder Within an Hour
People with treatment-resistant bipolar disorder experienced
relief from symptoms of depression in as little as 40 minutes
after an intravenous dose of the anesthetic medication ketamine
in a preliminary study; while the patient group was small, this
work adds to evidence that compounds in the class to which
ketamine belongs have potential as rapid and effective
medications for depression, including bipolar depression. The
potential for side-effects makes ketamine an impractical drug
for standard use, but it provides a way to test this approach
for developing novel treatments that act more rapidly than
existing ones.
Background
Bipolar disorder (BD) is a potentially debilitating illness
marked by severe swings in mood, energy, and behavior. Episodes
of depression alternate with spells of mania but depressive
episodes tend to be more frequent and longer-lasting and the
depression is difficult to treat. BD is usually treated with
mood stabilizing medications such as lithium, valproate,
carbamazepine or other medications with the goal of preventing
mood episode relapse. Antidepressant medications are often used
in addition to a mood stabilizer for depressive episodes, but
antidepressants typically take weeks to have an effect and many
patients do not respond adequately to existing medications.
Previous research has suggested that a disruption of signaling
between neurons involving the neurotransmitter glutamate is
likely to play a role in depression. The anesthetic medication
ketamine shuts down one class of receptor for glutamate (NMDA
receptors).
This Study
Eighteen people with BD participated in this study of ketamine.
All received maintenance treatment with a mood stabilizer
medication during the study. All had previously been
unsuccessfully treated with at least one antidepressant
medication and a mood stabilizer; the average number of
medications they had tried unsuccessfully was seven.
In the first phase of the study, each person was randomly
assigned to receive a single dose of either intravenous ketamine
or placebo (saline). After two weeks, treatment was switched, so
those initially receiving ketamine received placebo, and vice
versa. Neither patients nor those treating them were told
whether they were receiving ketamine or placebo. Investigators
used standard surveys of depression symptoms to assess the
effect of medication.
Within 40 minutes, 9 of 16 (56 percent) patients receiving
ketamine had at least a 50 percent reduction in symptoms, and 2
of 16 (13 percent) became nearly symptom-free. The response to
ketamine lasted an average of about a week. By contrast, no
patients receiving placebo had declines in symptoms close to the
magnitude seen with ketamine within the first 3 days.
Significance
In this study, carried out by scientists Nancy Diazgranados,
Carlos Zarate, Jr., and colleagues at the Experimental
Therapeutics & Pathophysiology Branch of NIMH's intramural
research program, a single intravenous dose of ketamine brought
relief from depression in severely treatment resistant patients
with BD, in over half of them within 40 minutes. This study
supports a previous one by the same group in which they also
found a rapid antidepressant effect in patients with
treatment-resistant major depression (unipolar). (NIMH press
release, August 7, 2006). The authors note that the rapid
antidepressant response observed in these two different
disorders (major depressive disorder and bipolar disorder)
highlights the importance of the NMDA receptor in developing
treatments with a rapid onset of action.
The work adds to the evidence of the potential of medications
targeting the glutamate system for rapid relief from depression,
even in cases of people who have failed to respond to other
existing therapies. Rapid and effective treatment of depression
is an urgent public health need. BD can be disabling—nearly all
the patients in this study were unemployed as a result of the
severity of their illness. BD is among the psychiatric disorders
with the highest risk of suicide.
Continuing research is focusing on developing NMDA-targeting
medications that are suitable for clinical use; and
investigating the use of this class of drugs for long-term
maintenance of the rapid antidepressant effect seen in this
study.
Reference
Diazgranados, N., Ibrahim, L., Brutsche, N.E., Newberg, A.,
Kronstein, P., Khalife, S., Kammerer, W. A., Quezado, Z.,
Luckenbaugh, D.A., Salvadore, G., Machado-Vieira, R., Manji,
H.K., and Zarate, C. A randomized add-on trial of an
N-methyl-D-aspartate antagonist in treatment-resistant bipolar
depression. Archives of General Psychiatry 2010;67(8):793-802.
For information on this study and other research conducted at
NIMH please see
HTML http://patientinfo.nimh.nih.gov/
or email:
nimhcore@mail.nih.gov, telephone 301-496-5645.
*****************************************************
Page 1 of 1