Ketamines For Depression

Depression is a serious mental disorder affecting millions of individuals worldwide. According to the World Health Organization, depression is the leading cause of disability worldwide. Traditional antidepressants, like selective serotonin reuptake inhibitors, are the mainstay treatment of depression. However, these drugs take weeks to show improvement, and some patients do not respond to them at all. Ketamine, a dissociative anesthetic, has demonstrated rapid and significant antidepressant effects in patients with treatment-resistant depression (TRD). This article will discuss what ketamine is, how it works, its efficacy in treating depression, and the potential side effects.

What is Ketamine?

Ketamine is a synthetic drug widely used as an anesthetic agent in humans and animals for surgical procedures. Its ability to induce dissociative or out-of-body experiences and pain control has made it popular among recreational drug users. Ketamine acts on a specific receptor in the brain called the N-methyl-D-aspartate (NMDA) receptor. This receptor plays a crucial role in learning and memory, and its malfunction is implicated in depression.

How Does Ketamine Work?

Ketamine works by stimulating the production of a brain-derived neurotrophic factor (BDNF) and inhibiting the function of certain glutamatergic pathways. BDNF is a protein that promotes the growth and survival of neurons, particularly in the hippocampus, a brain region involved in mood regulation. Glutamate is a neurotransmitter that stimulates the NMDA receptor, and studies have shown that reduced activity of this receptor contributes to depression. By promoting the production of BDNF and inhibiting the function of certain glutamatergic pathways, ketamine increases the activity of the NMDA receptor, leading to improvements in mood and cognition.

What is Treatment-Resistant Depression?

Treatment-resistant depression (TRD) is a form of depression that persists even after patients have undergone two or more previous antidepressant treatments. TRD is a significant challenge in clinical psychiatry, affecting up to one-third of patients with depression. Patients with TRD are more likely to have a chronic and severe form of depression, impairment in social and occupational functioning, and a higher risk of suicide. Several mechanisms contribute to the development of TRD, including genetic factors, comorbidities, and patient-related factors.

How Effective is Ketamine in Treating Depression?

Clinical trials have demonstrated a rapid and robust antidepressant effect of ketamine in patients with TRD. In a randomized controlled study, patients with TRD received a single intravenous infusion of ketamine at a dose of 0.5mg/kg or midazolam, a sedative drug, as a placebo. The ketamine-treated group showed a significant decrease in depressive symptoms compared to the midazolam group within 24 hours of administration. Improvement in mood persisted for up to seven days following the ketamine infusion. Another study found that 70% of patients with TRD showed a significant reduction in depressive symptoms after receiving a course of ketamine infusions over two weeks, and this effect was maintained for up to six months.

What are the Potential Side Effects of Ketamine?

Ketamine can cause several side effects, especially at higher doses. Acute side effects include an out-of-body sensation, hallucinations, confusion, and disorientation. These side effects typically resolve within a few hours following administration. Long-term use of ketamine has been associated with cognitive dysfunction and urological toxicity. However, the doses used in the treatment of depression are much lower than those used for anesthesia and administered by a healthcare professional.

Conclusion

Ketamine is a promising treatment option for patients with TRD. Its rapid and robust antidepressant effect makes it a valuable alternative to traditional antidepressants. However, its long-term safety and efficacy still require additional research, and it should only be used in patients who have failed to respond to other treatment options. Healthcare professionals should closely monitor patients receiving ketamine and provide adequate support throughout the treatment course. Nonetheless, the approval of several ketamine-based antidepressant drugs by regulatory authorities indicates that the benefits of ketamine in treating depression outweigh the potential risks.

FAQs

1. What is Ketamine and how does it work for depression?

Ketamine is an anaesthetic drug that has been found to have rapid antidepressant effects. It works by inhibiting a specific receptor in the brain, leading to increased glutamate levels and synaptic connections between neurons. This can lead to a decrease in symptoms of depression.

2. Is Ketamine safe for treating depression?

While Ketamine has been found to have rapid and significant antidepressant effects, there are still concerns about its long-term safety and potential for abuse. Therefore, Ketamine is currently only available for depression treatment in controlled settings and under the guidance of a trained medical professional.

3. How effective is Ketamine for treating depression?

Studies have shown that Ketamine can have a significant impact on improving symptoms of depression, with some patients reporting improvement within hours of treatment. However, the effects of Ketamine are not long-lasting, and additional treatments may be necessary to sustain improvement. It is important for patients to work closely with their medical professional to determine the best treatment plan for their individual needs.


References

1. Browne, C. A., Smith, M. A., & Zhou, Y. (2020). Recent advances and clinical translational implications of ketamine and esketamine in mood disorders. Clinical psychology review, 82, 101931. (Italic, Grey and size 8pt)

2. Lener, M. S., Kadriu, B., Lally, N., & Zarate Jr, C. A. (2017). Ketamine and beyond: investigations into the potential of glutamatergic agents to treat depression. Drugs, 77(4), 381-401. (Italic, Grey and size 8pt)

3. Zheng, W., Cai, D. B., Yang, X. H., Ungvari, G. S., Ng, C. H., Müller, N., … & Xiang, Y. T. (2019). Adjunctive ketamine for the treatment of depression: A systematic review and meta-analysis. Journal of psychiatric research, 117, 1-9. (Italic, Grey and size 8pt)