Study Indicates Ketamine Works Quickly on Depression

Depression is a serious mental illness affecting many Americans. More specifically, according to the American Psychiatric Association, approximately 10-25% of women in the United States and 5-12% of men will suffer from Major Depressive Disorder at some point in their lives. Anti-depressant medication is a common treatment for depression today. However, typical anti-depressants take weeks or even months to take effect. Due to the fact that some individuals with depression possess suicidal ideation, researchers are trying to develop a faster-acting anti-depressant. A recent study indicates ketamine helps relieve depression in a matter of hours.

Dr. Ronald Duman, who is a professor of pharmacology and psychiatry at Yale University, and his colleagues recently discovered that ketamine may be reformulated to create a fast-acting anti-depressant. Ketamine is typically utilized as an anesthetic. It is also used recreationally and is known as, "Special K."

The researchers injected rats with ketamine and noticed that the rats' depressive behaviors improved. They also noticed that synapses that had previously been destroyed in the rats' brain by chronic stress were restored with ketamine. Duman asserts that a reduction in the number of synapses (connections) in the prefrontal cortex are believed to be associated with depression. Duman and his colleagues discovered that synapses in the brains of rats were restored within 24 hours of receiving ketamine.

The researchers note that ketamine activates the mammalian target of repamycin (mTOR) signaling cascade, according to Chemical and Engineering News. The mTOR signaling cascade is concerned with synaptic changes and the creation of proteins in neurons. Ketamine prevents Glutamate, a neurotransmitter, from binding to the N-methyl-D-aspirate (NDMA) receptors located on neurons, which activates this pathway, according to Chemical and Engineering News.

The researchers assert these results may be significant in developing a fact-acting anti-depressant. They also declare that medications that activate these pathways may be alternative medications to those already on the market. Most of the anti-depressants currently available work by boosting neurotransmitters, such as norepinepherine and serotonin in the brain.

Ketamine may also be useful for individuals who are treatment-resistant to depression. According to Medical News Today, a previous study discovered over two-thirds of individuals who are treatment-resistant showed improved depressive symptoms hours after receiving ketamine.

While ketamine appears to be useful for treating individuals with depression, there are problems with using it as a viable treatment for this mental illness. First, ketamine doses must be given intravenously (through an IV). Second, the effects of ketamine on depression only last approximately one week, according to Medical News Today. Finally, this drug can produce temporary psychotic side-effects, such as hallucinations.

Major depression is a serious mental illness, which is fatal in some cases due to suicide attempts. The symptoms of depression include: an inability to concentrate or indecisiveness, loss of energy or feeling fatigued, feeling depressed nearly all day everyday, changes in sleeping patterns (hypersomia or insomnia), psychomotor retardation or agitation, experiencing inappropriate or excessive guilt or feelings of worthlessness, loss of interest in daily activities, and significant weight gain or weight loss when not attempting to diet. Individuals with depression may also possess recurrent suicidal thoughts or thoughts about death, have a suicide plan, or attempt suicide.

Researchers hope to take their knowledge about how ketamine works in the brain to reformulate it and develop fast-acting anti-depressants. If you would like to learn more about this study, you may visit the August 20 on-line edition of the journal Science.

Sources:

Chemical and Engineering News: Anti-Depressant's Unusual Speed Explained:
http://pubs.acs.org/cen/news/88/i34/8834notw3.html

Medical News Today: New Form of Ketamine Treats Depression "Like Magic:"
http://www.medicalnewstoday.com/articles/198483.php

American Psychiatric Association. ( 2000). Diagnostic and Statistical Manual of Mental Disorders IV-TR.