As a society, we are gradually moving away from the stigma placed on mental illness and recognizing that depression isn’t simply a sign of weakness or a low phase that someone can be “talked out of." Clinical depression or major depressive disorder is a serious illness that comes with real physical symptoms, including disturbances in diet and sleep, a lack of energy and a constant feeling of hopelessness. The World Health Organization estimates that as of 2017, there are 300 million people living with depression around the world. It is the most common mental illness in the US and despite a century of ongoing research, the antidepressants currently available are largely ineffective.

“Depression is caused due to a chemical imbalance in the brain.”

We hear it everywhere. Whether taught in textbooks or circulated around by drug advertisements, it is one of the most widespread beliefs held about clinical depression. It is also a myth. Antidepressants claim there is a chemical imbalance; however, recent studies say otherwise.

There is no evidence that a lack of serotonin causes depressed moods.

It’s been drilled into our minds that serotonin is the “feel good” hormone. For decades, low levels of serotonin have been correlated to depressed moods. But, the truth is, the evidence for such an association is quite slim. According to the 2006 STAR*D trial (the largest clinical test of antidepressants), less than a third of patients respond to antidepressants within 14 weeks. The number only increases to about a half after six months. For someone who has depression, that is a long time. Research also reveals that reducing levels of serotonin in healthy people did not make them emotionally sad. In fact, a study reported that depressed patients had increased levels of serotonin in their brains. Regardless, this idea that depression is caused due to a lack of serotonin continues to be widespread.

You might wonder how serotonin even emerged as a candidate to explain depression. Here is a brief history:

In 1954, after finding that LSD is processed in the brain similar to serotonin, D. W. Woolley concluded that the neurotransmitter plays a role in brain signaling and that its deficit could lead to mental illness. Drugs such as iproniazid and imipramine were originally intended to treat schizophrenia and tuberculosis. Yet, due to their elevated levels of serotonin, patients reported feeling very happy.

One experiment was enough to be taken as concrete evidence for the long-lived myth of chemical imbalance!

And so began the search for antidepressants. The first drugs called MAOIs and tricyclic antidepressants were great, except they required strict diets and carried adverse side effects. Coming in hot in the '80s, selective serotonin reuptake inhibitors (SSRIs) were more specifically focused on serotonin and brought huge commercial success. Today, Prozac, Zoloft, and Paxil are prescribed in increasingly great quantities, even though they are unsuccessful in treating depression.

The problem lies in the lack of awareness. Patients trust their doctors to be well informed, but they have to realize that in the end, everything is a business and money must be made. If continuously prescribing ineffective drugs to patients is necessary to keep the profits going, then that is the reality.

So, what is depression actually caused by? We still don’t know. There are many guesses out there, but a conclusive answer is yet to arrive. Current research suggests that depression is related to structural changes in the brain, primarily caused by stress. Early childhood trauma, loss of a loved one, divorce, poor living conditions, you name it. Everyone’s response to stress is different and varies on genetics and individual experience. A mishap might be a minor bump in the road for some, but devastating for others, making them prone to depression.

Ketamine is a psychedelic club drug that could potentially stop suicidal thoughts and act as vaccination against depression and PTSD. Typically used as an anesthetic, studies on mice have shown it to be highly effective in treating depression. Low doses of ketamine have yielded faster and better results in 65% of patients who are unresponsive to existing antidepressants.

The only problem is that pharmaceutical companies and doctors have little to no incentive to invest in ketamine. For starters, the process to approve it as an antidepressant is long and requires funding by pharma companies. Although cheap and generic versions of ketamine are available, they cannot be monetized either. Why? The cheaper alternative is lithium carbonate. Because lithium is an element, it cannot be patented. The good news is, pharmaceutical companies are looking for other alternatives that would be less trippy and unpleasant than ketamine.

Of course, other treatments for depression do exist. Talk therapy, electroconvulsive therapy, psychotherapy are just a few to name. Suicide is among the top ten leading causes of death, with 90% of those committing suicide affected with some mental illness. Are we going to continue failing to save people for the sake of business? Should doctors let millions continue to struggle with depression throughout their lives? Is it worth it?