Ketamine Rapidly Relieves Depression by Restoring Brain Connections
10/05/2012 — Nancy Sajben MD
This research is one of the most dramatic findings in the field of depression and mood disorders. It was published in Science by researchers from Yale and the National Institute of Mental Health, discussed by PBS here.
The speed with which ketamine can relieve major depression is deeply moving to witness. In my experience prescribing nasal ketamine it works almost 100% of the time. I have discussed ketamine and previous publications on it for Major Depression and PTSD. It is also effective for suicidal and bipolar depression patients.
Ronald S. Duman, PhD, the lead scientist, reviews his group’s research in this 2011 video:
Stress and depression leads to structural changes in the brain and these structural changes are reversible.
Depression affects 17% of the population, almost one in five of the population. Only one third of patients are effectively treated by existing antidepressants, even after many weeks. Nerve growth factors, in particular BDNF, are decreased by stress, with a very significant loss in depressed patients. BDNF produces antidepressant behavior in rodent models of depression.
BDNF is important for influencing the survival and function of neurons.
There are certain neurogenic zones in the brain that produce new neurons. Stress decreases the number of new neurons. Chronic antidepressant use increases the numbers and proliferation of these new neurons. Antidepressant treatment increases neurogenesis and this is dependent upon BDNF, this neurotrophic factor.
[His slide shows] Exercise, Prozac, ECT, antipsychotics, antidepressants increase neurogenesis.
Not only are there more synapses made by ketamine, but they are a larger size which is indicative of ones that are more functionally connected. Antidepressants take many weeks. A single dose of ketaminerapidly reverses depressive behaviors and loss of connections and completely reverses the decrements that had occurred over several weeks.
In suicidal patients given ketamine at Yale in the Emergency Room, within a matter of hours, the suicidality is completely reversed. These people are better for weeks after a single dose of ketamine treatment. [emphasis mine]
Therapeutically ketamine is even more rapidly acting than ECT.
Ketamine increases BDNF. But research shows its effects are blocked in mice that are deficient in BDNF. Riluzole also influences BDNF, but the side effect profile is so serious that I would not consider prescribing it without more data on safety.
Safety concerns are often raised in publications regarding chronic ketamine use. Most of my patients have no side effects at all. It is one of the safest medications we have and only a small percentage experience transient side effects. The favorable side effect profile, simplicity and low cost is key. The results for nasal ketamine are not 100%, neither is IV ketamine, but I have patients who respond to nasal spray when they failed IV ketamine. More importantly, they can carry it in their pocket and use as needed.
My experience prescribing ketamine goes back almost to the year 2000 for persons with chronic pain who have used ketamine several times daily, and since Spring 2012 for Major Depression. Its effect for depression lasts longer than for chronic intractable pain where it is short lasting. In the past, I prescribed it orally, by mouth, but since late 2011 I have prescribed it in a nasal spray and that form works for depression.
The neuroprotective action of ketamine has been published since at least 1988.
Patients can use nasal ketamine as needed. Schedules vary, everyone is different. It is short acting, but it does not stop working.
However, the use of other adjuvants, such as glial modulators, in treatment of depression is essential to understand, and is now work in progress. The role of inflammation and glia in the pathogenesis of depression has been well established since 2000, and discussedhere.
Does ketamine also restore brain connections in patients with chronic pain? Chronic pain and major depression both lead to brain atrophy and memory loss. Both cause the same imbalance in glial cytokines. Both may respond to glial modulators, e.g. low dose naltrexone among others that have worked in some patients.
“The original link between ketamine and relief of depression was made at the Connecticut Mental Health Center in New Haven by John Krystal, chair of the department of psychiatry at Yale, and Dennis Charney, now dean of Mt. Sinai School of Medicine, who helped launch clinical trials of ketamine while at the National Institute of Mental Health,” reported by Yale here.
I hope to add new approaches to treatment of anxiety that has failed to respond to other interventions.
Original Article- http://painsandiego.com/2012/10/05/ketamine-rapidly-relieves-depression-by-restoring-brain-connections/