Berberine HCl is a relatively unknown health supplement, especially when you consider the powerful health benefits that it can generate. Berberine is extracted from the Berberine vulgaris plant and is used to help promote healthy blood sugar levels. It has a huge amount of research showing the its therapeutic potential.
Berberine side effects are often overlooked because of the low Bereberine toxicity rating. However, there are definitely some side effects of Berberine to look out for, which is what we’ll explore in this article. We also look into three great Berberine stacks to boost the health benefits!
What does Berberine Do?
Berberine is one of the few dietary supplements available today with sufficient evidence to show that it is as effective as some pharmaceuticals. It is one of the best supplements available today to lower blood sugar.
This is especially important in the Western world, where type 2 diabetes is so prevalent. In 2016, the percentage of Americans living with diabetes was estimated to be just under 10%. This equates to a staggering 29.1 million people living with diabetes in America.
Other potential benefits of Berberine include: anti-inflammatory effects, helps to destroy cholesterol, works as a powerful antioxidant, reduces fat in the liver, improves insulin sensitivity, and reduces triglycerides. For more information about Berberine’s great benefits, check out our article on the <Top 8 Berberine benefits>.
Berberine Recommended Dosage
The recommended daily Berberine dosage to lower blood sugar is around 1500mg. Researchers have found that this dosage may be equally effective in lowering blood sugar as 1500mg of metformin or 4mg glibenclamide. 
You can take Berberine 500 mg, three times daily, to reach the correct recommended dosage. Using separate doses avoids potential gastrointestinal side effects like stomach cramps and nausea.
Top 5 Berberine Side Effects:
1. Interacts with medication
Although Berberine is considered a very safe dietary supplement with a low toxicity and few side effects, it has the potential to interact with a large number of medications. For this reason, we do not recommend using Berberine HCl if you are taking any other type of medication.
Please speak to your doctor if you’re taking any medication and would like to use a Berberine vulgaris extract. The most important Berberine interactions include:
- May potentiate (increase) the effects of drugs that lower blood sugar. This is primarily due to Berberine’s blood sugar lowering effects.
- Berberine inhibits certain cytochromes: CYP2D6, CYP2C9, and CYP3A4. These cytochromes are the targets of a large number of medications, and by using Berberine HCl with other medication, you run a risk of potential dangerous side effects.
- Berberine has a powerful effect on anion transporter proteins in the cell membrane. A few medications use these transporters to access your cells and deliver their effects. One important medication is Metformin – a prescribed compound for type 2 diabetes.
2. High doses may cause diarrhea, stomach cramps
Berberine toxicity is considered to be extremely low. It is a very safe dietary supplement and natural plant extract. The few Berberine side effects include mild gastrointestinal discomfort at high doses. It’s useful to know that Berberine was once used as a treatment for diarrhea.
Berberine’s absorption in your stomach is less-than-optimal due to the action of a number of enzymes. These enzymes affect the efficiency of Berberine’s uptake. This is why, at high doses, the few side effects of Berberine can include:
- Stomach cramps
- Gastrointestinal discomfort
In order to avoid these side effects, doctors and scientists recommend taking a daily Berberine HCl dosage in three separate servings. This equates to a Berberine 500 mg dosage three times per day. Using a lower dosage prevents upsetting your stomach and allows you to avoid the gastrointestinal side effects of Berberine.
Despite the potential side effects at high doses, researchers have praised Berberine for it’s mild side effects when compared to other substances that lower blood sugar. For example, the metformin and diarrhea side effect is a powerful one that causes problems for many people.
3. Dangerous interaction with macrolide antibiotics
One important and potentially dangerous interaction to mention is Berberine with macrolide antibiotics. There is evidence that Berberine can interact with a certain class of antibiotics called macrolide antibiotics. These include the antibiotics azithromycin and clarithromycin.
The Berberine toxicity occurs at hERG channels in the heart. There is a potential for serious negative health effects in these interactions. Please make sure that you avoid taking Berberine if you are using antibiotics, especially macrolide antibiotics.
On another note, Berberine may also have powerful antibiotic and antimicrobial effects. Recent studies have indicated that Berberine may have a synergistic relationship with some antibiotic medications.  Multidrug resistance (MDR) pump inhibitors may also increase Berberine’s antibiotic activity. 
Top 3 Berberine Stacks:
1. Berberine with P-Glycoprotein inhibitors
P-Glycoprotein is involved in the absorption of Berberine by your stomach. It seems that P-Glycoprotein contributes to the poor absorption of Berberine. Animal studies have shown that combining Berberine with a P-glycoprotein inhibitor can increase the Berberine absorption rate by up to 6 times! 
Many P-glycoprotein inhibitors are research chemicals or laboratory-made compounds. These tend to have acceptable toxicity ratings, but can be difficult to obtain and may have unwanted side effects.
Some natural P-glycoprotein inhibitors are found in certain plant chemicals like flavonoids and stilbenes. Natural sources include:
- Baicalein and Baicalin
- Grape fruit juice
- Milk thistle
- Stephania tetrandra 
2. Berberine with Sodium Caprate
Sodium caprate (also known as decanoic acid) is a research chemical with a number of applications in science. It has been studied for its benefits in improving the absorption of many chemical compounds in medicine.
Recent Berberine reviews have found that Sodium caprate significantly helps to improve the absorption of Berberine vulgaris extracts. Research suggests that Berberine has a fairly poor rate of absorption in your stomach. Sodium caprate improves the transport of Berberine into the blood from your stomach.
3. Berberine with Quercetin
Quercetin is a great dietary supplement to use with Berberine HCl. Quercetin is a plant-derived compound with a number of great benefits. The combination of Berberine and Quercetin may have a synergistic relationship and helps to provide a host of <health benefits>.
Like Berberine, Quercetin is a powerful antioxidant. It helps to neutralize potentially dangerous free-radicals in your body.  Quercetin is also a potent anti-inflammatory supplement and may help to reduce allergic responses. It has been shown to aid in cardiovascular health and to support healthy blood-pressue.
While Quercetin doesn’t have as much research data as Berberine HCl does at this time, the evidence is certainly out that it is a powerful health supplement. Taken together, Berberine and Quercetin create a powerful health stack.
In conclusion, Berberine is a safe dietary supplement to use on its own. It may have a synergistic relationship with a number of other health-promoting substances. Research is still being compiled about the synergistic relationship of Berberine with other health-promoting supplements.
The recommended Berberine dosage is around 1500 mg per day, taken in two to three separate doses. Taken alone, Berberine toxicity is very low.
Berberine side effects may include gastrointestinal discomfort and nausea at high doses. An important note is that Berberine may interact with a large number of medications, causing potentially dangerous health effects. If you are taking any other medication, please speak to your doctor to help avoid the side effects of Berberine interactions.
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