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Are Probiotics Making You Feel Sick? (Updated 2023)

Are Probiotics Making You Sick


Probiotics are one of the most popular health categories for supporting immunity, digestion and mood. Scientific evidence shows probiotics may even have a positive effect on cognitive function. With all these great benefits, why do some people feel worse or even sick when taking a new probiotic? We will discuss this phenomenon and ways you can minimize potential discomfort.

MicrobiomeThe Complexity of the Microbiome

Our microbiome is extremely complicated and diverse, containing over 100 trillion bacteria and comprises 70% of our immune system. It has a major impact on energy, metabolism, and our overall wellbeing. These trillions of bacteria coexist and interact within a diverse and intricate ecosystem of fungus, nutrients, minerals and complex chemical processes. Probiotic containing foods and supplements have become a staple in the diets of millions of individuals to help maintain the health of this complex ecosystem.

So, can probiotics actually make us sick?

It is possible for probiotics to stimulate a detox reaction that can lead to a litany of symptoms that can vary from mild to miserable. This occurs when probiotics rapidly starve out unwanted organisms, causing metabolic byproducts to be released into the body. For instance, dead yeast cells over time can release up to 80 different toxins including uric acid, ethanol, and acetaldehyde, a potent neurotoxin. If you have ever started taking a probiotic and felt exhausted, feverish, or had flu-like symptoms, it may be linked to this type of detox effect, also known as a Herxheimer reaction. The medical community is well aware of Herxheimer reactions when people are treated for serious illnesses, such as certain bacterial infections, other autoimmune conditions or even after heavy rounds of antibiotics.

Detox Sickness

Am I taking the wrong probiotic?
Experiencing detox symptoms does not necessarily mean that you are taking a poor-quality product, and one could even argue that it’s an indication that the product is working. However, well-formulated products can be effective while also minimizing detox-related symptoms.

Things to keep in mind with probiotic supplements in particular is that a product containing dozens of different strains of bacteria or the highest CFU count is not always more effective and, in some cases, can have an adverse effect on efficacy. Common grocery store probiotics tend to simply be formulated to offer the most CFU activity for the most inexpensive price, so they appear appealing on a shelf, but with little to no thought into actual strain quality or make-up. Often labeled as containing tens of billions of CFUs per capsule at their time of manufacture, only a tiny fraction of the CFU activity typically survives the time on a shelf, let alone the digestive process or the intestinal environment.

Designing the ideal Probiotic

Less Risk for DetoxCountless hours and careful consideration went into developing our best-selling probiotic formula Syntol. Syntol is a daily probiotic, but so much more, combining prebiotics as well as probiotic spores and enzymes. Probiotic spores or “seeds” are superior to typical probiotics, as they are not as susceptible to acidic digestion and are extremely shelf stable. Spores germinate in the intestinal tract, attaching to the intestinal wall and have much higher survivability than non-spores, quickly restoring intestinal balance. Syntol’s Acid Armor® delivery capsules further defend against acidic breakdown by defending the ingredients from stomach acid.

Syntol’s enzyme and probiotic blend was specifically designed to minimize probiotic detox. Specialized enzymes are added to breakdown the organisms responsible for toxins and the probiotics are carefully selected non-competitive strains that do not interfere with other strains in your microbiome. This unique formula helps to cleanse the digestive system while limiting the uncomfortable detox. Syntol’s unique ingredients help digest dead and decaying organisms away before they can release potential chemicals and toxins, which helps to limit potential symptoms or signs of detox.

blood slide before


Subject suffers from fatigue and digestive issues.* Headache & Insomnia.  

blood slide after


Subject indicated energy levels are at a ten year high and digestion returned to normal.*

What should I do if I still experience a detox?

  • Continue to take your probiotic supplement. Although uncomfortable, this period should pass in in no more than 7 days.
  • Cut your dose in half and/or take your probiotic every other day to lessen symptoms.
  • Take your probiotic with food. Probiotics are more effective when taken on an empty stomach, but while you aren’t feeling your best, take with food for 7 days. You can change to taking on an empty stomach after your body has adjusted.
  • Be aware that combining Syntol with other probiotics, antifungals, and/or herbal detox products can intensify any detox reaction.

For more information about the benefits of Syntol Click Here.

Frequently asked questions in 2023

Why do I feel sick after taking probiotics?

Probiotics are beneficial live bacteria and yeasts that can promote good health, especially in the digestive system. However, some individuals may experience side effects after taking probiotics. There could be various reasons why you feel sick after taking probiotics. For example, taking an excessive dose can overwhelm the gut with an abundance of bacteria, leading to probiotic overload. Introducing new strains of bacteria to the gut can also cause temporary digestive disruptions such as bloating, gas, and constipation, leading to gut disruption. Additionally, low-quality products may contain harmful additives or not contain the strains and amounts of bacteria listed on the label. Finally, allergic reactions can occur if you have a known allergy to any of the ingredients in the probiotics.

Can you feel sick when starting probiotics?

It is not uncommon to feel sick when starting probiotics, and many people experience some level of digestive upset. Introducing new strains of bacteria to the gut can take time for the body to adjust, and temporary digestive disruptions such as bloating, gas, and constipation may occur. These symptoms usually subside within a few days to a week as the body adapts to the new bacteria. However, if the symptoms persist or worsen, it is essential to consult a healthcare professional.

What are symptoms of too much probiotics?

While probiotics are generally safe and beneficial for most people, taking too much can cause negative side effects. The symptoms of too much probiotics include digestive upset such as bloating, gas, and diarrhea, as well as more severe symptoms such as skin rashes and allergic reactions. It is crucial to start with a lower dose of probiotics and gradually increase it over time to allow the body to adjust and avoid taking too much.

Are there any negative effects of probiotics?

Although probiotics are generally safe, there are some potential negative effects to be aware of. In rare cases, probiotics can lead to infections in people with weakened immune systems or other underlying health conditions. Probiotics may also interact with certain medications, such as antibiotics and immunosuppressants. Therefore, it is crucial to talk to a healthcare professional before starting probiotics if you're taking any medications or have a weakened immune system. Finally, if you experience persistent symptoms or have any concerns, it's important to talk to a healthcare professional before continuing to take probiotics.


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