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Should I be tired on antibiotics?

Antibiotics are a class of drugs used to treat bacterial infections in the human body. They are powerful drugs that can help eliminate infections when taken properly. However, many people who take antibiotics report feeling tired or fatigued while on the medication. This leads to a common question many people have: should I be tired on antibiotics?

How Antibiotics Work

Before diving into why people may feel tired on antibiotics, it’s important to understand how antibiotics work. Antibiotics are designed to kill bacteria or prevent bacteria from growing. They do this by targeting certain areas of the bacterial cell, such as the cell wall or the enzymes that bacteria need to survive. When antibiotics are successful in killing or slowing the growth of bacteria, the body’s immune system can work more effectively to eliminate the infection.

Do Antibiotics Cause Fatigue?

While antibiotics do not directly cause fatigue, there are a few reasons why some people may experience fatigue while taking antibiotics. For one, when the body is fighting off an infection, it requires a lot of energy to do so. This can make you feel tired or fatigued, regardless of whether you are taking antibiotics or not.

Another reason why people may feel tired on antibiotics is due to the impact antibiotics can have on the gut microbiome. The gut microbiome is made up of a complex system of bacteria and other microorganisms that live in the digestive system. Antibiotics can disrupt this delicate balance by killing off both harmful and beneficial bacteria in the gut. When this happens, it can lead to digestive issues, such as diarrhea and bloating, which can make you feel more tired or fatigued.

How to Deal with Fatigue on Antibiotics

While fatigue is a common side effect of antibiotics, there are things you can do to help manage it. The most important thing to do is to give your body plenty of rest. When the body is fighting off an infection, it requires a lot of energy to do so. Make sure to get plenty of sleep, and don’t overexert yourself while on antibiotics.

Another way to help deal with fatigue on antibiotics is to take care of your gut health. Since antibiotics can disrupt the gut microbiome, taking a probiotic supplement can help rebalance and replenish the beneficial bacteria in your gut. Eating probiotic-rich foods, such as yogurt and fermented foods, can also help support your gut health. Additionally, drinking plenty of water and eating a healthy, balanced diet can help support your immune system and give your body the nutrients it needs to fight off the infection.


In summary, antibiotics do not directly cause fatigue, but some people may feel more tired or fatigued when taking them. This is often due to the body’s increased energy needs while fighting off an infection or disruption to the gut microbiome caused by the antibiotics. While fatigue can be a bothersome side effect, there are things you can do to manage it, such as getting plenty of rest, taking care of your gut health, and staying hydrated and well-nourished. If you do continue to experience severe fatigue or other concerning symptoms while on antibiotics, talk to your doctor.

For more information on gut health and probiotics, check out this healthline article.


What are the most common side effects of antibiotics?

Antibiotics are medications that are used to treat bacterial infections, but they can also cause some unwanted side effects. While antibiotics can be highly effective at fighting infections, they can have a range of side effects that vary from person to person.

One of the most common side effects of antibiotics is a rash. This can occur anywhere on the body and vary in severity from a mild rash to a more severe reaction that requires medical attention. Another common side effect of antibiotics is dizziness. This can be caused by the medication affecting the inner ear, leading to feelings of lightheadedness or vertigo.

Nausea is another common side effect of antibiotics. This may be caused by the medication irritating the stomach or intestines. Sometimes, diarrhea may also occur. This is because antibiotics can affect the balance of bacteria in the gut. In some cases, this can lead to a condition called Clostridioides difficile infection (also known as C. difficile or C. diff). This is a serious infection that can cause severe diarrhea and colon damage, and it can even be fatal.

Women who take antibiotics may also be at risk of developing a yeast infection. This is because antibiotics can disrupt the balance of bacteria in the vagina, leading to an overgrowth of yeast.

It’s important to note that while antibiotics can have side effects, they are still an essential treatment for bacterial infections. Doctors always weigh the risks and benefits of prescribing antibiotics, and only use them when they are necessary. If you experience any side effects while taking antibiotics, it’s important to let your doctor know so that they can monitor your condition. In some cases, your doctor may adjust your medication or prescribe additional medications to help manage any side effects that you are experiencing.

Can antibiotics cause sleeplessness?

In general, most antibiotics do not cause sleeplessness or insomnia. However, there have been some reports of sleep disturbances in patients taking certain antibiotics, such as levofloxacin, which is a type of fluoroquinolone antibiotic. Levofloxacin has been associated with acute insomnia, which is characterized by difficulty falling asleep or staying asleep for a period of up to several days.

Antibiotics work by fighting bacterial infections in the body, and they are usually prescribed for short-term use. Therefore, even if someone does experience sleep disturbances while taking an antibiotic, it is typically a temporary issue that resolves once the course of antibiotics is completed.

If you are experiencing difficulty sleeping while taking antibiotics, it may be helpful to talk to your healthcare provider. They may be able to recommend strategies to help you sleep better, such as adjusting the timing of your medication or suggesting other sleep aids that are safe to take with antibiotics.

It is important to note that while some antibiotics can cause sleep disturbances, there are other factors that can contribute to insomnia or sleeplessness as well. These include stress, anxiety, certain medications, and issues with sleep hygiene. If you are experiencing persistent sleep difficulties, it is a good idea to speak with your healthcare provider to identify the underlying cause and develop an appropriate treatment plan.

Why do I feel worse after starting antibiotics?

Antibiotics are designed to treat infections caused by bacterial microorganisms. However, the use of antibiotics can sometimes result in unexpected side effects, one of which is the phenomenon of feeling worse after starting antibiotic treatment. Antibiotic use can cause a range of symptoms that include nausea, vomiting, diarrhea, and abdominal discomfort. Patients receiving antibiotics may also experience other symptoms such as a loss of appetite, difficulty sleeping, and physical fatigue.

One of the root causes of these symptoms is the impact that antibiotics have on the gut microbiome, which is the community of microorganisms that live in the intestines and play a crucial role in maintaining overall health. Antibiotics can disrupt this microbiome by wiping out not only bad bacteria but also beneficial microorganisms that play important roles in digestion and the immune system.

The gut microbiome is incredibly important for the body, as it is responsible for producing vitamins, breaking down food, and most notably, supporting the immune system. The gut is said to be the center of immunity and is home to the largest concentration of immune cells in the body. When antibiotics kill both the good and bad bacteria in the gut, it can impact the body’s immune system, leaving it vulnerable to further infections.

Additionally, antibiotics cause changes in the gut that disrupt normal fermentation, leading to an overgrowth of bacteria that thrive in an oxygen-deprived environment. This can cause further digestive symptoms like bloating and gas, making one feel worse.

While antibiotics are essential to treat bacterial infections, they can cause side effects and lead to a range of symptoms. Disruption of the gut microbiome, changes in normal fermentation, and changes in the immune system can cause a patient to feel worse after starting antibiotic treatment. It often takes some time for the gut microbiome to recover to its previous state, so it’s essential to support the gut with probiotics, prebiotics, and a healthy diet during and after taking antibiotics.