1/4 of All Drugs Сan Сause Fatigue-Study
Not just antibiotics
Scientists have long found a direct link between the brain and the gut.
Many of us are well aware that antibiotics can kill our friendly gut bacteria, and this affects our well-being and mood.
But more recently, medical scientists managed to identify the exact mechanism by which these drugs lead to increased physical fatigue, decreased stamina, and even the suppression of motivation to do something that requires us to exert effort.
The findings were published in the journal Nature in December 2022.
This discovery is more applicable to animals so far. Nevertheless, what you will learn today will probably convince you that it is not just about animals, and most surprisingly, not just about antibiotics.
I did some additional research and found some very valuable information that nicely complements the results of this study
The problem is much broader and deeper than previously thought.
Researchers at the University of Pennsylvania found that taking broad-spectrum antibiotics reduces the number of bacteria involved in energy production by the body, resulting in mice not only getting tired faster but also having less interest in physical activity.
In this case, the key factor for such “laziness” and low stamina was a decrease in the number of metabolites produced primarily by two species — Eubacterium rectale, and Coprococcus eutactus.
These microbes live in the gut and produce fatty acid amides. The amides stimulate receptors in the cells of the peripheral nervous system, which in turn increases dopamine levels in the brain.
For one thing, it has long been known that low levels of dopamine correlate with increased fatigue. For example, we can see this in patients with Parkinson’s disease. It is also associated with mental fatigue in people with multiple sclerosis.
Of course, your fatigue isn’t necessarily related to our topic today. But if you’re taking several different medications, your risk is very high, especially if you notice chronic fatigue after starting a new medication. Talk to your doctor about it.
Chemical “ laziness” can be accompanied by a psychological loss of desire to exercise, because, as I said earlier, the hormone dopamine not only increases desire but in fact gives a pleasant feeling of anticipation.
But what pleasant anticipation can we talk about in a state of total brokenness after even moderate exercise?
“A good aftertaste gives sweet anticipation”- Byha-health
Of course, not everything in our lives has to be accompanied by pleasure and passion. Nevertheless, for many, it is a key motivating factor.
A study on rats clearly showed that a decrease in the level of the hormone dopamine in the brain negatively affects willpower and motivation to overcome difficulties for the sake of greater rewards in animals.
Conversely, an increase in dopamine made the rats even more inclined to overcome challenges for more tasty snacks.
In simple terms, with suppressed dopamine production, you are more likely to prefer an easier job to a harder one, even if you can get paid a lot more for the latter.
A study involving human subjects found that people with low levels of dopamine are more likely to refuse a greater reward if it requires more effort to obtain it.

But besides money, many other things can be our reward
- good health
- sports achievements
- Getting 6-pack (or even 8-pack) abs.
Dopamine should not be too much. It is enough when it is not too little.
Our task is to find the true cause of our condition, or as Uncle Albert used to say:
“The formulation of the problem is often more essential than its solution, which may be merely a matter of mathematical or experimental skill.” - Albert Einstein
Let me return to fatty acid amides, which are produced by bacteria in our intestines.
Fatty acid amides (FAA) affect various processes in the body. In addition to affecting our mood and appetite, it also:
- relieves pain
- reduces inflammation
- induces sleep
- and relaxes blood vessels and muscles.
Certainly, these properties of fatty acid amides seem familiar to many readers.
Most of us feel this sensation after great physical activity, after a long exercise. Of course, if we are not forced to do it against our will.
To some of you, these feelings may seem similar to those experienced with cannabinoids. And those people would be right too!
The fact is that fatty acid amides, which are produced with the help of intestinal bacteria, are in fact natural analogs of cannabidiols, or so-called endocannabinoids, which do not cause negative mental side effects and even prevent them.
Here one might be tempted to use medical cannabis to combat fatigue, pain, and inflammation. However prolonged use of these substances can lead to analgesic tolerance. It doesn’t solve the problem fundamentally. Especially since quite often medical cannabis leads to undesirable side effects, including cognitive and mental.
In my opinion, it is much more effective to start treating the root cause.
To do that, you have to find it first. As you have already realized, the source of the problem may be hiding in your gut. But should we hold our focus only on antibiotics?
Here’s where it gets really interesting.
Not many people know about it, but in fact, antibiotics are not the only drugs that can cause an imbalance of beneficial bacteria in the intestines.
In confirmation of these words, I want to share with you the results of research, which showed that about a quarter of all drugs can negatively affect intestinal microbiota!
The bacteria we are talking about today are some of the most sensitive to all kinds of medications. And we’re not talking about mice anymore.
It’s about us human beings. How about this?
These bacteria, among other things, are involved in the production of butyrate, a metabolite that is involved in energy metabolism and inflammation, and protect the intestinal barrier, thereby protecting you from irritable bowel syndrome.
Moreover, scientists have already found a link between chronic fatigue syndrome of unknown etiology and a decrease in the relative abundance of these bacteria.
I hope and believe that this information will help someone get closer to the root of their problem, and find the best way to solve it with your doctor.
However, there are natural and safe foods that can improve the balance of bacteria, which I have told you about today. They will not solve the problem at its root, but they can partially improve the condition of a part of the people suffering from gut-related chronic fatigue. I will share this valuable information with you after a more in-depth analysis of the subject.
Get email reminders 📧 when my new health stories come out.
You can motivate me to write more stories like this and get unlimited access to all Medium stories by becoming my Referral.






