August 26, 2024

Alex Moss  

12th Grade

Alfred Barbe High School

With about 280 million people around the world suffering from depression, it has become one of the most common mental disorders affecting people. According to the CDC, in 2020, 18.4% of adults reported being diagnosed with depression. Approximately one-fifth of Americans had a diagnosis of depression. The disorder can present as a spectrum as there are many different ways it can manifest itself in someone's life. Treatments for depression vary severely. The most common method of treatment is a medication branch known as antidepressants. Currently, the four main branches of antidepressants consist of SSRIs (Selective Serotonin Reuptake Inhibitors), SNRIs (Serotonin/Norepinephrine Reuptake Inhibitors), MAOIs (Monoamine Oxidase Inhibitors), and TCAs (Tricyclic Antidepressants). 

The origins of antidepressants began in the 1950s in a research lab meant to be treating tuberculosis. Scientists pioneered iproniazid, a type of drug that affected monoamine neurotransmitters. This drug did not manage to treat tuberculosis effectively; however, several patients seemed to be in much better moods. Iproniazid became classified as the first antidepressant, specifically under the classification of an MAOI. MAOIs and TCAs are older forms of antidepressants that are not used often in modern medicine as much anymore. SSRIs are the most common form of antidepressant currently prescribed. Drugs such as Zoloft and Prozac are the most commonly prescribed SSRIs mainly due to their lack of many side effects compared to MAOIs.

Each of the antidepressants functions similarly as they each work on the body’s absorption, otherwise known as reuptake, of monoamine neurotransmitters such as serotonin, norepinephrine, and dopamine. Reuptake is a biochemical process and the focal point of how antidepressants work. When a pre-synaptic and post-synaptic neuron communicate with neurotransmitters the pre-synaptic will later absorb the neurotransmitters it released. This means that the post-synaptic neuron is no longer affected by those neurotransmitters. In cases of depression, reuptake can occur too fast meaning the post-synaptic neuron does not get the optimal amount of time to absorb the neurotransmitters needed to become excited or inhibited. Antidepressants increase the amount of time specific monoamine neurotransmitters are within the synapse by closing the reuptake channels. One of the main receptors these drugs affect would be 5-HT neurons, such as those found within the raphe nuclei and cortico-limbic areas. The raphe nuclei are a part of the brainstem that is responsible for the production of serotonin. Researchers are now finding that only 5% of the serotonin in the body is made in the raphe nuclei, whereas 95% of our serotonin is made within our gut. With this in mind, researchers are questioning if current antidepressants are as effective as they can be.