Rethinking Depression: A new drug for depression

Nov 17
The treatment of Depression was revolutionized when Prozac was approved as the first antidepressant by the US FDA in 1987. Antidepressant drugs work on the neurotransmitters of the brain by inhibiting certain signals and increasing the activity of other signals. The popular belief surrounding depression is the Monoamine Hypothesis: that depression is the result of underactivity of monoamines, the specific neurotransmitters that are responsible for different functions in the brain. The effect antidepressants were having on people made sense in this hypothesis: brains with underactivity of monoamines get treated with monoamines, and the result is a happier person. However, a long standing problem with the hypothesis is that antidepressant medication can immediately raise levels of monoamines however the symptoms of depression take on average take 3 to 5 weeks to abate and additionally, only work on 60% of the patients. This warrants asking if the Monoamine Hypothesis is the complete picture of depression.

Ketamine, a staple anesthetic in emergency rooms, has been around since the 1960s. Often used as a recreational drug, ketamine has anesthetic and dissociative properties based on the dose. In a small case study in 2006, the National Institute of Mental Health discovered when ketamine was administered to 18 treatment-resistant, depressed patients, depression symptoms improved within one day in 71% of those given ketamine. This discovery sheds light on our understanding of antidepressant mechanisms in the brain.

Ketamine is currently not US FDA approved, however clinics are emerging with Ketamine as a treatment option for otherwise treatment-resistant patients. Another concern with Ketamine is that there is not enough evidence for treatment of depression with ketamine to determine its safety in chronic use. While research is not a high priority for pharmaceutical companies, companies are trying to develop and test new molecules that have similar effects as ketamine.

One example is esketamine. “By changing its formulation so that it can be administered in the form of a nasal spray, … esketamine [becomes] easier to use than isometrically mixed ketamine and creates something patentable. Preliminary evidence suggests esketamine does indeed work, and the [company] is seeking approval for it to be used to treat two conditions: major depressive disorder with imminent risk of suicide, and treatment-resistant depression.”

Exploring the use of new depression medication such as ketamine is also key for understanding and preventing mental health conditions through an understanding of the mechanisms that work. Changes in the medical community and in gold-standard practices require rigorous testing and solid evidence of efficacy and effectiveness. Once approved however, much of this information remains in the knowledge banks of a few, especially in the field of mental health. A dedicated team of mental health professionals partaking in knowledge translation and knowledge dissemination can enhance the individual’s understanding of mental health concerns and treatment, and play a leading role in their mental health and well-being. 

2006 Study Abstract: 
2013 Study: Antidepressant Efficacy of Ketamine in Treatment-Resistant Major Depression: A Two-Site Randomized Controlled Trial: