How Different Antidepressants Work

I’ve taken some excerpts from WebMD explaining how antidepressants work. Please click here for the link if you care to read it in its entirety.

Note: Using WebMD as a source is not necessarily an endorsement of WebMD. While they have much good information, they also promote misinformation, especially when discussing diet and nutrition. Consider this:

Cut back on Fats and Oils: Eating too many fats can cause high cholesterol and heart disease. With DASH [Dietary Approaches to Stop Hypertension], you’ll limit fats and oils to two to three servings a day. A serving is 1 teaspoon of margarine or vegetable oil, 1 tablespoon of mayonnaise, or 2 tablespoons of low-fat salad dressing. When cooking, use vegetable oils like olive or canola instead of butter.

Soybean oil, canola oil, and cottonseed oil are the worst of the worst fats and should be avoided. For those that followed our reviews and digests of Dr. Stephen Sinatra’s The Great Cholesterol Myth, these already oxidized, seed-based* oils are high in Omega 6 fatty acids. Omega 6 oil are very unstable when heated *Calling them vegetable oils is a misnomer. You get oil from seeds, not vegetables.

Factory, high temperature processing causes these oils to become rancid or oxidized by the time you buy them. Because they are rancid, they throw off free radicals right and left.  When you consume them, this contributes to turning harmless, low-density lipo-proteins into bad cholesterol which in turn, leads to inflammation of your coronary arteries.

Yes, WebMD is still on the bandwagon of demonizing cholesterol. The fact that a supposed “health” website supports the use of margarine, a transfat, suggests that they have an agenda, one that does not have your health in mind.

WebMD has a bias that favors the use of pharmaceutical drugs and processed factory foods. Sites such as WebMD may also be the recipient of hidden corporate sponsorship. If a soybean oil processor, for example, is funding WebMD, that gives WebMD motive for demonizing butter and promoting seed [vegetable] oils and soy-based foods. Condoning the use of margarine, a transfat, is a dead giveaway.

For more revealing information about WebMD, please click here and here.

With these caveats in mind concerning WebMD, let’s learn about the pharmacology behind commonly prescribed antidepressants.

Reuptake Inhibitors: SSRIs, SNRIs, and NDRIs

…We really don’t know what causes depression or how it affects the brain. We don’t exactly know how antidepressants improve the symptoms.

That said, many researchers believe that the benefits of antidepressants stem from how they affect certain brain circuits and the chemicals (called neurotransmitters) that pass along signals from one nerve cell to another in the brain. These chemicals include serotonin, dopamine, and norepinephrine. In various ways, different antidepressants seem to affect how these neurotransmitters behave. Here’s a rundown of the main types of antidepressants…

Some of the most commonly prescribed antidepressants are called reuptake inhibitors. What’s reuptake? It’s the process in which neurotransmitters are naturally reabsorbed back into nerve cells in the brain after they are released to send messages between nerve cells. A reuptake inhibitor prevents this from happening. Instead of getting reabsorbed, the neurotransmitter stays — at least temporarily — in the gap between the nerves, called the synapse.

What’s the benefit? The basic theory goes like this: keeping levels of the neurotransmitters higher could improve communication between the nerve cells — and that can strengthen circuits in the brain which regulate mood.

My comment: simply put, an SSRI slows down the use or reuptake of your serotonin, causing it to last longer in your nerve synapses.


Different kinds of reuptake inhibitors target different neurotransmitters. There are three types:

Selective serotonin reuptake inhibitors (SSRIs) are some of the most commonly prescribed antidepressants available. They include Celexa, Lexapro, Luvox, Paxil, Prozac, and Zoloft. Another drug, Symbyax, is approved by the FDA specifically for treatment-resistant depression. It’s a combination of the SSRI antidepressant fluoxetine (Prozac) and another drug approved for bipolar disorder and schizophrenia called olanzapine (Zyprexa). Aripiprazole (Abilify), quetiapine (Seroquel), and brexpiprazole (Rexulti) have been FDA approved as add-on therapy to antidepressants for depression. Plus, doctors often use other drugs in combination for treatment-resistant depression. Also, the drugs  vilazodone (Viibryd) and vortioxetine (Trintellix – formelrly called Brintellix) are among the newest antidepressants that affect serotonin. Both drugs affect the serotonin transporter (like an SSRI) but also affect other serotonin receptors to relieve major depression.

Serotonin and norepinephrine reuptake inhibitors (SNRIs) are among the newer types of antidepressant. As the name implies, they block the reuptake of both serotonin and norepinephrine. They include duloxetine (Cymbalta), venlafaxine (Effexor), desvenlafaxine ER (Khedezla), levomilnacipran (Fetzima), and desvenlafaxine (Pristiq).

Norepinephrine and dopamine reuptake inhibitors (NDRIs) are another class of reuptake inhibitors, but they’re represented by only one drug: bupropion (Wellbutrin). It affects the reuptake of norepinephrine and dopamine.

My comments: In doing Part D prescription plan searches for clients, I have frequently run across the classic SSRIs such as fluoxetine, sertraline, and citalopram. I found it helpful to understand that venlafaxine and duloxetine are SNRIs and that bupropion is an NDRI. Note: These are the generic names for brand name drugs.


Older Antidepressants: Tricyclics and MAOIs

These drugs were among the first to be used for depression. Although they’re effective, they can have serious side effects and can be especially dangerous in overdose. Nowadays, many doctors only turn to these drugs when newer — and better tolerated — medicines haven’t helped. Tricyclics and MAOIs might not be the best approach for someone who was just diagnosed. But they can sometimes be very helpful for people with treatment-resistant depression, or certain forms of depression (such as depression with anxiety).

Tricyclic antidepressants (TCAs) include amitriptyline (Elavil), desipramine (Norpramin), imipramine (Tofranil), and nortriptyline (Pamelor). Like reuptake inhibitors, tricyclics seem to block the reabsorption of serotonin and epinephrine back into nerve cells after these chemicals are released into a synapse. Because of the potential side effects, your doctor might periodically check your blood pressure, request an EKG, or recommend occasional blood tests to monitor the level of tricyclics in your system. These medicines might not be safe for people with certain heart rhythm problems.

My comments: I found it helpful to learn that amitriptyline and nortriptylineare in an older class of antidepressants. It was also interesting to note that these drugs are prescribed when the newer antidepressants haven’t worked. Using WebMD. Reading this section about antidepressants was the longest time that I have used this website. One criticism that a reviewer on had of WebMD was the tediousness of reading the site for information because of the bombardment of advertisements and popups. I found the same to be true. Nevertheless, despite the shortcomings and conflicts of interest concerning WebMD, it is possible to ferret out some useful information. End


The articles in Northwest Senior News are for your education and general health information only, and the opinions of various writers do not necessarily reflect those of Northwest Senior News. The ideas, opinions and suggestions contained in Northwest Senior News are NOT to be used as a substitute for medical advice, diagnosis or treatment from your doctor for any health condition or related issues. Readers of Northwest Senior News should not rely on information provided in these articles for their own healthcare. Any questions regarding your own healthcare should be addressed to your own physician. Please do NOT start or stop any medications or any other medical protocol without consulting your doctor or other licensed healthcare practitioners.