Posts Tagged Ketamine

[WEB PAGE] How New Ketamine Drug Helps with Depression

Yale psychiatrists, pioneers of ketamine research, shed light on new FDA approval

An illustration of a woman suffering from depression who might be helped by esketamine

The FDA approval of esketamine gives doctors another valuable tool in their arsenal against depression—and offers new hope for patients no one had been able to help before. “This is a game changer,” says John Krystal, MD, chief psychiatrist at Yale Medicine and one of the pioneers of ketamine research in the country.

On March 5, the Food and Drug Administration (FDA) approved the first truly new medication for major depression in decades. The drug is a nasal spray called esketamine, derived from ketamine—an anesthetic that has made waves for its surprising antidepressant effect.

Because treatment with esketamine might be so helpful to patients with treatment-resistant depression (meaning standard treatments had not helped them), the FDA expedited the approval process to make it more quickly available. In one study, 70 percent of patients with treatment-resistant depression who were started on an oral antidepressant and intranasal esketamine improved, compared to just over half in the group that did not receive the medication (called the placebo group).

“This is a game changer,” says John Krystal, MD, chief psychiatrist at Yale Medicine and one of the pioneers of ketamine research in the country. The drug works differently than those used previously, he notes, calling ketamine “the anti-medication” medication. “With most medications, like valium, the anti-anxiety effect you get only lasts when it is in your system. When the valium goes away, you can get rebound anxiety. When you take ketamine, it triggers reactions in your cortex that enable brain connections to regrow. It’s the reaction to ketamine, not the presence of ketamine in the body that constitutes its effects,” he says.

And this is exactly what makes ketamine unique as an antidepressant, says Dr. Krystal.

However, as the nasal spray becomes available via prescription, patients have questions: How does it work? Is it safe? And who should get it? Read on for answers.

How do antidepressants work?

Research into ketamine as an antidepressant began in the 1990s with Dr. Krystal and his colleagues Dennis Charney, MD, and Ronald Duman, PhD, at the Yale School of Medicine. At the time (as is still mostly true today) depression was considered a “black box” disease, meaning that little was known about its cause.

One popular theory was the serotonin hypothesis, which asserted that people with depression had low levels of a neurotransmitter called serotonin. This hypothesis came about by accident—certain drugs given to treat other diseases like high blood pressure and tuberculosis seemed to drastically affect people’s moods. Those that lowered serotonin levels caused depression-like symptoms; others that raised serotonin levels created euphoric-like feelings in depressed patients. This discovery ushered in a new class of drugs meant to treat depression, known as selective serotonin reuptake inhibitors (SSRIs). The first one developed for the mass market was Prozac.

But eventually it became clear that the serotonin hypothesis didn’t fully explain depression. Not only were SSRIs of limited help to more than one-third of people given them for depression, but growing research showed that the neurotransmitters these drugs target (like serotonin) account for less than 20 percent of the neurotransmitters in a person’s brain. The other 80 percent are neurotransmitters called GABA and glutamate.

GABA and glutamate were known to play a role in seizure disorders and schizophrenia. Together, the two neurotransmitters form a complex push-and-pull response, sparking and stopping electrical activity in the brain. Researchers believe they may be responsible for regulating the majority of brain activity, including mood.

What’s more, intense stress can alter glutamate signaling in the brain and have effects on the neurons that make them less adaptable and less able to communicate with other neurons.

This means stress and depression themselves make it harder to deal with negative events, a cycle that can make matters even worse for people struggling with difficult life events.

Ketamine—from anesthetic to depression “miracle drug”

Interestingly, studies from Yale research labs showed that the drug ketamine, which was widely used as anesthesia during surgeries, triggers glutamate production, which, in a complex, cascading series of events, prompts the brain to form new neural connections. This makes the brain more adaptable and able to create new pathways, and gives patients the opportunity to develop more positive thoughts and behaviors. This was an effect that had not been seen before, even with traditional antidepressants.

“I think the interesting and exciting part of this discovery is that it came largely out of basic neuroscience research, instead of by chance,” says Gerard Sanacora, MD, PhD, a psychiatrist at Yale Medicine who was also involved in many of the ketamine studies. “It wasn’t just, ‘let’s try this drug and see what happens.’ There was increasing evidence suggesting that there was some abnormality within the glutamatergic system in the brains of people suffering from depression, and this prompted the idea of using a drug that targets this system.”

For the last two decades, researchers at Yale have led ketamine research by experimenting with using subanesthetic doses of ketamine delivered intravenously in controlled clinic settings for patients with severe depression who have not improved with standard antidepressant treatments. The results have been dramatic: In several studies, more than half of participants show a significant decrease in depression symptoms after just 24 hours. These are patients who felt no meaningful improvement on other antidepressant medications.

Most important for people to know, however, is that ketamine needs to be part of a more comprehensive treatment plan for depression. “Patients will call me up and say they don’t want any other medication or psychotherapy, they just want ketamine, and I have to explain to them that it is very unlikely that a single dose, or even several doses of ketamine alone, will cure their depression,” says Dr. Sanacora. Instead, he explains, “I tell them it may provide rapid benefits that can be sustained with comprehensive treatment plans that could include ongoing treatments with ketamine.  Additionally, it appears to help facilitate the creation new neural pathways that can help them develop resiliency and protect against the return of the depression.”

This is why Dr. Sanacora believes that ketamine may be most effective when combined with cognitive behavioral therapy (CBT). CBT is a type of psychotherapy that helps patients learn more productive attitudes and behaviors. Ongoing research, including clinical trials, addressing this idea are currently underway here at Yale.

A more patient-friendly version

The FDA-approved drug esketamine is one version of the ketamine molecule, and makes up half of what is found in the commonly used anesthetic form of the drug. It works similarly, but its chemical makeup allows it to bind more tightly to the NMDA glutamate receptors, making it two to five times more potent. This means that patients need a lower dose of esketamine than they do ketamine. The nasal spray allows the drug to be taken more easily in an outpatient treatment setting (under the supervision of a doctor), making it more accessible for patients than the IV treatments currently required to deliver ketamine.

But like any new drug, this one comes with its cautions. Side effects, including dizziness, a rise in blood pressure, and feelings of detachment or disconnection from reality may arise. In addition, the research is still relatively new. Studies have only followed patients for one year, which means doctors don’t yet know how it might affect patients over longer periods of time. Others worry that since ketamine is sometimes abused (as a club drug called Special K), there may be a downside to making it more readily available—it might increase the likelihood that it will end up in the wrong hands.

Also, esketamine is only part of the treatment for a person with depression. To date, it has only been shown to be effective when taken in combination with an oral antidepressant. For these reasons, esketamine is not considered a first-line treatment option for depression. It’s only prescribed for people with moderate to severe major depressive disorder who haven’t been helped by at least two other depression medications.

In the end, though, the FDA approval of esketamine gives doctors another valuable tool in their arsenal against depression—and offers new hope for patients no one had been able to help before.

To learn more, visit yalemedicine.org.

 

via How New Ketamine Drug Helps with Depression > Stories at Yale Medicine

, , , , , , ,

Leave a comment

[WEB SITE] Ketamine – More Than a Recreational Drug.

concert-1149979_1280

Ketamine was first introduced in 1962. It was initially presented as a fast acting general anesthetic, being widely used as a battlefield anesthetic in the 1970s. Ketamine is considered a dissociative anesthetic – it creates an altered state of consciousness, distorting the perception of sound and vision, and producing a feeling of detachment from oneself and from the environment which provides pain relief, sedation, and amnesia.

In the clinic, ketamine is mainly used for starting and maintaining anesthesia. Given its fast sedative action, it is frequently used in emergency situations. Its main effects usually begin within five minutes of injection and last up to 25 minutes.

But ketamine can have some impactful psychological side-effects as the medication wears off, such as agitation, confusion, or hallucinations. The latter is the main reason for its use as a drug of abuse or recreational drug. Ketamine began to be illicitly consumed in the 1970s and, nowadays, it is equally known for its medical and recreational use. Ketamine can produce illusions or hallucinations that are enhanced by environmental stimuli, which explains its popularity as a club drug.

Ketamine is still used in medical contexts as an anesthetic, although its use has become less common and more restricted. However, in recent years, a new use for ketamine has been emerging.

Ketamine as an antidepressant drug

Recent studies have shown that ketamine has fast antidepressant actions in patients with major depressive disorder, even in those with the most treatment-resistant forms of depression. Major depressive disorder is a highly disabling condition with limited treatment options that are often ineffective. The onset of depression is poorly understood but it is thought to derive from a combination of neurochemical factors and triggering life events, such as overwhelming stress. Potential neurochemical factors include defects in the major neurotransmitters of the central nervous system, glutamate and GABA.

Glutamate is the major excitatory neurotransmitter in the central nervous system. Experimental studies in animal models of depression have associated glutamate with depression, showing that there may be altered levels of glutamate receptors; increased glutamate concentrations have also been found in the brains of patients with major depressive disorder. Since ketamine acts by blocking the action of the NMDA glutamate receptors, this is a likely mechanism for its fast action in depression.

Indeed, a single dose of ketamine has been shown to be able to normalize the activity of glutamate receptors. Importantly, the effects of ketamine occurred only at low doses, indicating that these antidepressant effects can occur without the psychological side effects associated with high doses of ketamine.

GABA, on the other hand, is the major inhibitory neurotransmitter in the central nervous system. It has also been associated with depression – mice with an impairment of GABAergic transmission exhibit behavioral signs that mimic the emotional patterns of depression, which supports the view of a causal link between GABAergic neurotransmission and depression. Major depressive disorder has been linked to reduced levels of GABA and GABA receptors, and to reduced expression of glutamic acid decarboxylase, an enzyme that converts glutamate to GABA.

These two effects may seem contradictory, but these deficits in the GABAergic system may actually lead to increased glutamate concentrations. However, some studies have also reported reduced rather than increased brain levels of glutamate. This has led to the hypothesis that depression may actually be associated with a dynamic balance between changes in GABAergic and glutamatergic transmission. The mechanisms underlying this possible relationship were mostly unknown, but a new study published on the journalBiological Psychiatry sheds light on this subject.

A matter of balance

A stable and regular functioning of neural networks relies on an ability to maintain a balance between inhibitory and excitatory neurotransmission. In the mentioned study, and with the goal of understanding how the balance between GABA and glutamate levels may be linked to depression, the consequences of GABAergic deficits on glutamatergic synapses were investigated. It was found that mice with depression associated with GABAergic deficits also showed reduced expression and function of glutamate receptors.

A decrease in the number and activity of glutamatergic synapses was also found. Treatment with a sub-anesthetic dose of ketamine led to a lasting normalization of glutamate receptor levels and glutamatergic synapse function. These results indicate that depression in mice with impaired GABAergic neurotransmission involves a balancing reduction of glutamatergic transmission that can be normalized for a prolonged period of time by the rapidly acting antidepressant ketamine.

This study thereby establishes the link between the GABAergic and glutamatergic deficits described for depression, and suggests that it may be caused by a dysregulation of the equilibrium mechanisms that act to restore the balance of excitation and inhibition. It is possible that conditions of chronic or repeated stress, which may trigger the development of depression, may do so by affecting the balance between GABA and glutamate levels, or by impairing the mechanisms that could restore that balance. Indeed, chronic stress has been shown to decrease the production of glutamate receptors and to render GABAergic inhibition ineffective.

This work also reinforced the antidepressant efficacy of ketamine. However, ketamine will always have a huge drawback due to its drug-of-abuse properties. The use of other NMDA glutamate receptor antagonists without the side-effects of ketamine has been tested with promising results, leading to similar effects as those obtained with ketamine. Here may lay the answer.

References

Garcia, L., Comim, C., Valvassori, S., Réus, G., Stertz, L., Kapczinski, F., Gavioli, E., & Quevedo, J. (2009). Ketamine treatment reverses behavioral and physiological alterations induced by chronic mild stress in rats Progress in Neuro-Psychopharmacology and Biological Psychiatry, 33 (3), 450-455 DOI:10.1016/j.pnpbp.2009.01.004

Hashimoto, K., Sawa, A., & Iyo, M. (2007). Increased Levels of Glutamate in Brains from Patients with Mood Disorders Biological Psychiatry, 62 (11), 1310-1316 DOI: 10.1016/j.biopsych.2007.03.017

Ionescu, D., Luckenbaugh, D., Niciu, M., Richards, E., Slonena, E., Vande Voort, J., Brutsche, N., & Zarate, C. (2014). Effect of Baseline Anxious Depression on Initial and Sustained Antidepressant Response to Ketamine The Journal of Clinical Psychiatry, 75 (09) DOI: 10.4088/JCP.14m09049

Jansen, K. (2011). A Review of the Nonmedical Use of Ketamine: Use, Users and Consequences Journal of Psychoactive Drugs, 32 (4), 419-433 DOI:10.1080/02791072.2000.10400244

Li, N., Lee, B., Liu, R., Banasr, M., Dwyer, J., Iwata, M., Li, X., Aghajanian, G., & Duman, R. (2010). mTOR-Dependent Synapse Formation Underlies the Rapid Antidepressant Effects of NMDA Antagonists Science, 329 (5994), 959-964 DOI:10.1126/science.1190287

Luscher, B., Shen, Q., & Sahir, N. (2010). The GABAergic deficit hypothesis of major depressive disorder Molecular Psychiatry, 16 (4), 383-406 DOI:10.1038/mp.2010.120

Morgan, C., Curran, H., & , . (2012). Ketamine use: a review Addiction, 107 (1), 27-38 DOI: 10.1111/j.1360-0443.2011.03576.x

Niciu, M., Ionescu, D., Richards, E., & Zarate, C. (2013). Glutamate and its receptors in the pathophysiology and treatment of major depressive disorderJournal of Neural Transmission, 121 (8), 907-924 DOI: 10.1007/s00702-013-1130-x

Ren, Z., Pribiag, H., Jefferson, S., Shorey, M., Fuchs, T., Stellwagen, D., & Luscher, B. (2016). Bidirectional Homeostatic Regulation of a Depression-Related Brain State by Gamma-Aminobutyric Acidergic Deficits and Ketamine TreatmentBiological Psychiatry DOI: 10.1016/j.biopsych.2016.02.009

Image via Unsplash / Pixabay.

Source: Ketamine – More Than a Recreational Drug | Brain Blogger

, , , , ,

Leave a comment

[WEB SITE] Ways to Treat Depression That Aren’t Antidepressants

Feb. 27, 2015 — There may be hope for hard-to-treat depression as scientists explore novel ways to help people who have the often crippling condition.

Recently, a number of studies have suggested the benefits of Botox, ketamine, and certain sometimes-unexpected means of treating depression.

“I’m excited in general, and I’m curious,” says Peter D. Kramer, MD, author of Listening to Prozac and Against Depression.

Each year, around 16 million U.S. adults battle major depression. Many of them benefit from antidepressants. But as many as a third get depressive symptoms despite medication. And side effects, which can include weight gain, nausea, and insomnia, are troublesome for some patients. That leaves many people with depression searching for alternatives.

But if Kramer is hopeful about the newer, novel ways to treat the condition, he’s also cautious. The studies backing those treatments aren’t conclusive, and none of the approaches have been approved by the FDA to treat depression (though some, such as ketamine, have been approved for other uses).

“Things are merely hopeful until they are demonstrated [safe and effective],” Kramer says. “It’s always hard to tell what’s going on, but it’s a very interesting time, and I think some of them will come through.”

Here’s a closer look at what might be used to help treat depression in years to come.

Ketamine. Already in use in certain clinics and in some emergency departments around the country, ketamine is an anesthetic most often used during surgery. It’s given through an IV, and it quickly eases symptoms of depression, often in a matter of hours. The benefit is temporary, though.

One recent study found it to be very good at helping curb suicidal thoughts in severely depressed people. But it’s expensive, still experimental as a depression treatment, and can cause hallucinations and other side effects.

“Some people are very uncomfortable with the side effects,” says Alan Manevitz, MD, a psychiatrist who specializes in treatment-resistant depression at Lenox Hill Hospital in New York City.

Nitrous oxide, or laughing gas. This is an anesthetic commonly used by dentists. A small study published last December reports that nitrous oxide improved depression symptoms within less than 2.5 hours.

Continue–> Ways to Treat Depression That Aren’t Antidepressants.

, , , , , ,

Leave a comment

[WEB SITE] Ketamine therapy: New, innovative treatment for depression in the Valley

SCOTTSDALE, AZ – The Valley has one of the first Ketamine clinics in the country — with the newest innovation fighting depression to help you or your family.

Colorful History

Ketamine is more commonly known as a horse tranquilizer. In the ’90s, crooks stole Ketamine out of veterinarian clinics to sell on the street as ‘Special K.’ It was a popular rave drug.

But, Ketamine really got its start during the Vietnam War. It was used as an anesthetic. It’s also used in emergency rooms across the country.

Today, it’s the hottest new method for treating clinical depression.

Treating Depression

The clinic is called, Depression Recovery Centers and it is located in Scottsdale. There, patients receive small doses of the drug intravenously while being closely monitored at the clinic. “We are seeing incredible results,” said Dr. Ellen Diamond, a clinical psychologist at the clinic. “I have seen person after person come through here and their life has been changed.”

Ger Gaines is the clinic’s owner. He made his first fortune as one of the founders of Sprint PCS. Now, he’s taking on clinical depression. “Depression is very common. About 10 percent of the population has depression at any given time,” he said.

But for Gaines, it is more than just a business venture. “I suffer from bipolar disorder,” he said, “But probably more motivating, I have close relatives that also suffer from depression. And just being able to do something that can change their lives is important to me.”

Ketamine treatment for depression was found accidently. It was being used for pain relief when many of the patients noticed they weren’t depressed anymore. “We are more directly targeting the structures in the brain that control emotions,” Diamond said.

Gaines uses “dead leaves on a tree” as an analogy. “What the Ketamine does is take that unhealthy looking tree in winter and grow it back to a tree in summer in just an hour’s time.”…

more–> Ketamine therapy: New, innovative treatment for depression in the Valley – ABC15 Arizona.

,

Leave a comment

‘Anti-ketamine’ to treat depression – Medical News Today

Ketamine works by blocking one of the targets for the neurotransmitter glutamate in the brain, the N-methyl-D-aspartate (NMDA) glutamate receptor.

Now, a new study in Biological Psychiatry reports that enhancing, instead of blocking, that same target – the NMDA glutamate receptor – also causes antidepressant-like effects.

via ‘Anti-ketamine’ to treat depression – Medical News Today.

,

Leave a comment

%d bloggers like this: