Supplements haven't been tested for safety and due to the fact that dietary supplements are largely unregulated, the content of some products may differ from what is specified on the produ… In addition to chloroquine, the nutraceuticals quercetin (bioflavonoid) and epigallocatechin-gallate (green tea polyphenol) are also zinc ionophores. There are some warnings about Quercetin side effects regarding interactions with medication, and it should not be used by pregnant or breastfeeding women. This article will tell you about the varied quercetin side effects. Side Effects of Quercetin. Quercetin is considered safe. Common side effects of quercetin include: Headache (oral use); Numbness and tingling (oral use) Shortness of breath (intravenous use); Nausea and vomiting (intravenous use); Kidney damage (intravenous use greater than 945 mg/m2); This document does not contain all possible side effects and others may occur. Quercetin Side Effects. In summary, Quercetin is a great supplement for anybody looking to boost their health and well-being. 2017 Mar 4;57(4):666-676. However, people who are sensitive to citrus and use quercetin in a formula containing vitamin C, or other citrus bioflavonoids might want to err with caution because some experts point out that some have reported mouth sores, headaches, and digestive upset. Some have reported tingling in the arms and legs, as well as upset stomach and headaches when taking quercetin orally.7 Very high doses—greater than 1 gram per day—might cause kidney damage. I have personally taken 3 capsules of quercetin and bromelain for 3 days in a row without side effects. High doses may cause headaches and an upset stomach. 2011;701:283-9. Minor side effects may result from quercetin supplement use, such as blurred vision, swollen feet, and ankles, dizziness, fluid accumulation in the knee, dull ache or feeling of pressure or heaviness in legs, headache, itching skin near damaged veins, pounding in the ears, nervousness, or a slow or fast heartbeat. Like many other plant flavonols, Quercetin has powerful anti-inflammatory effects. The present review is dedicated to safety aspects of isolated quercetin … When taken by mouth, quercetin can cause headache and tingling of the arms and legs. Side Effects. [11]. [2], Quercetin has powerful beneficial effects on your circulatory system. This article explores quercetin’s uses, benefits, side effects, and dosage. [8], In a study published in 2009 in the British Journal of Nutrition, researchers found that 6 weeks of daily dosing with 150mg of Quercetin had no negative impacts on liver or kidney health, and that participant’s blood and electrolyte levels remained healthy too, indicating that regular, long-term Quercetin supplementation is safe. You must have JavaScript enabled in your browser to utilize the functionality of this website. The anti-inflammatory effects that have been shown in cell cultures of both human and animal cells. Not intended to treat, diagnose, or cure any disease or ailment. These statements have not been reviewed by the FDA and are not written by a medical professional. Luckily, Quercetin side effects are minimal and this plant-based dietary supplement is generally considered safe at the recommended dosages. This would equate to around 900 – 1800mg per day for a 75kg person. Quercetin Side Effects – Thyroid, Allergies, Tingling, Upset Stomach Quercetin is a natural flavonoid found abundantly in fruits and vegetables, especially – raspberries, apples, red grapes, red onions, citrus fruits, cherries, and green leafy vegetables. Note: This document contains side effect information about bioflavonoids. The flavonoid quercetin is frequently found in low amounts as a secondary plant metabolite in fruits and vegetables. 1. You may report them to the FDA. [1] Y Li et al., “Quercetin, Inflammation and Immunity”, Nutrients. Quercetin is a nutritional supplement that is derived from plants and fruits. Quercetin FDA Alerts. Taking quercetin along with some medications that are broken down by the liver can increase the effects and side effects of these medications. Very high doses of quercetin may damage the kidneys. Quercetin is generally well-tolerated when used in appropriate amounts. Fighting free radicals. Capable of blocking “mast cells,” which are immune cells critical … Side effects of Quercetin in dogs. Supplemental doses of over 1000mg per day have sometimes been associated with mild headaches and stomach aches, and very high doses delivered by intravenous injection have been associated with kidney failure. Adverse reacations with long term supplementation over several years is not known. Examples include Quercetin with Green Tea Extract catechins and polyphenols, with Taurine, and with Baicalin. Quercetin, which has a long story of usage in human history, has been demonstrated sufficient efficacy and has no significant side effects. More clinical studies would need to determine the side effects of quercetin in different formulations and doses. At this time quercetin side effects have been reported in the medical literature. Quercetin may also help to improve energy levels and to reduce stress. The most common side effect of quercetin is the allergic reactions that it causes in some people. Some side effects of bioflavonoids (the active ingredient contained in Quercetin) may occur that usually do not need medical attention. That said, they do state two possible side effects for users to be aware of: Headaches Upset Stomach WebMD says that quercetin has been used safely in a dosage up to 500 mg twice a day for a period of 12 weeks. Available for Android and iOS devices. Conclusion. Quercetin plus zinc is being tested as an anti-viral in human clinical trials for the treatment of Covid-19. Quercetin may also interact with a number of medications and other supplements: Quercetin has not been established as safe for use by pregnant or breastfeeding women. Taking quercetin along with some medications that are broken down by the liver can increase the effects and side effects of these medications. [10]. Although quercetin is usually considered safe for consumption, you may experience side effects such as upset stomach and headache, states the UMMC. Following is a list of possible medication recalls, market withdrawals, alerts and warnings. However, proper safety trials are lacking . Quercetin is one of the most important plant molecules, showing pharmacological activity such as antiviral, anti‐atopic, pro‐metabolic, and antiinflammatory effects. Quercetin is believed to be safe for dogs, but should not be given to dogs with kidney disease or dogs who are being given blood-thinning medication or antibiotics. [3] M Barteková et al., “Quercetin improves postischemic recovery of heart function in doxorubicin-treated rats and prevents doxorubicin-induced matrix metalloproteinase-2 activation and apoptosis induction”, Int J Mol Sci. Please consult your doctor before using any supplements, especially if you have any medical conditions. Most studies have found little to no side effects in people eating diets high in quercetin or taking supplements short term. What is Quercetin? The FDA Alert(s) below may be specifically about Quercetin or relate to a group or class of drugs which include Quercetin. Most people experience no side effects with quercetin, but some individuals have reported headache and/or tingling in the limbs. Quercetin is a natural pigment present in many fruits, vegetables, and grains. We comply with the HONcode standard for trustworthy health information -, dull ache or feeling of pressure or heaviness in legs. First of all, University of Maryland Medical Center considers quercetin safe. 2016 Mar; 8(3): 167. Most studies on Quercetin have incorporated a standard dosage of around 12.5 to 25mg per kg bodyweight, per day. Before taking quercetin, talk with your healthcare provider if you take any medications that are changed by the liver. These side effects may go away during treatment as your body adjusts to the medicine. This dose can be separated into two or three servings throughout the day. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. It can be found in high quantities in red wine, onions, green tea, apples, berries, and Gingko Biloba. Side Effects, Risks, and Interactions. There are some warnings about Quercetin side effects regarding interactions with medication, and it should not be used by pregnant or breastfeeding … Some common sense in respect to the quercetin dosage you choose can go a long way to curbing negative quercetin side effects. The easiest way to lookup drug information, identify pills, check interactions and set up your own personal medication records. Animal studies have indicated that Quercetin may have strong stress-reducing benefits. It has also been demonstrated to have a wide range of anticancer properties, and several reports indicate its efficacy as a cancer‐preventing agent. It is also a powerful antioxidant. This means that it helps to destroy reactive chemical species called ‘free-radicals’ which cause damage to your body and can have negative impacts on the health of your circulatory system. According to the University of Queensland medical center, Quercetin is generally considered safe for use. Two of the greatest Quercetin benefits are its ability to support a healthy immune system and to work as a powerful anti-inflammatory supplement. In the present study, we have evaluated the effects of quercetin on the expression of other thyroid-restricted genes, and we show that quercetin decreases the expression of the thyrotropin receptor, thyroid peroxidase and thyroglobulin genes. JavaScript seems to be disabled in your browser. If you’d like to find out more about Quercetin for dogs, we recommend booking an appointment with your veterinarian to talk about how you can use Quercetin to boost your dog’s health. Quercetin is generally thought to be safe to consume up to fairly high levels, particularly in dietary form. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Research has indicated that it can improve the recovery speed of the heart and help to reduce the effects of stress on the heart. 2006 Mar; 13(3): 319–328. [9], Believe it or not, Quercetin for dogs is something that many people are talking about today. But there’s even more to the story. The University health care page also suggests taking regular breaks from using Quercetin. Additionally, some preliminary evidence exists that quercetin may generate a byproduct, which leads to loss of protein function in your body. 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