
Background
Quercetin has antioxidant and anti-inflammatory effects that might help reduce swelling, kill cancer cells, control blood sugar, and help prevent heart disease.
Quercetin is most commonly used for conditions of the heart and blood vessels and to prevent cancer. It is also used for arthritis, bladder infections, and diabetes, but there is no strong scientific evidence to support most of these uses. There is also no good evidence to support using quercetin for COVID-19.
Safety Safety definitions
When applied to the skin: There isn't enough reliable information to know if quercetin is safe or what the side effects might be.
Special Precautions & Warnings:
Pregnancy and breast-feeding: There isn't enough reliable information to know if quercetin is safe to use when pregnant or breast-feeding. Stay on the safe side and avoid use.Kidney problems: Quercetin might make kidney problems worse. Don't use quercetin if you have kidney problems.
Effectiveness
- Athletic performance. Taking quercetin by mouth before exercise doesn't decrease fatigue or improve exercise ability.
Dosing & administration
Interactions with pharmaceuticals
Antibiotics (Quinolone antibiotics)
Interaction Rating=Moderate Be cautious with this combination.
Some scientists think that taking quercetin along with certain antibiotics, called quinolone antibiotics, might decrease the effects of these antibiotics. But it's too soon to know if this is a big concern.
Cyclosporine (Neoral, Sandimmune)
Interaction Rating=Moderate Be cautious with this combination.
Quercetin might decrease how quickly the body breaks down cyclosporine. Taking quercetin with cyclosporine might increase the effects and side effects of cyclosporine.
Diclofenac (Voltaren, others)
Interaction Rating=Moderate Be cautious with this combination.
Quercetin might decrease how quickly the body breaks down diclofenac. Taking quercetin with diclofenac might increase the effects and side effects of diclofenac.
Losartan (Cozaar)
Interaction Rating=Moderate Be cautious with this combination.
Quercetin might change how the body absorbs and breaks down losartan. Taking quercetin with losartan might change the effects and side effects of losartan.
Medications changed by the liver (Cytochrome P450 2C8 (CYP2C8) substrates)
Interaction Rating=Moderate Be cautious with this combination.
Some medications are changed and broken down by the liver. Quercetin might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.
Medications changed by the liver (Cytochrome P450 2C9 (CYP2C9) substrates)
Interaction Rating=Moderate Be cautious with this combination.
Some medications are changed and broken down by the liver. Quercetin might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.
Medications changed by the liver (Cytochrome P450 2D6 (CYP2D6) substrates)
Interaction Rating=Moderate Be cautious with this combination.
Some medications are changed and broken down by the liver. Quercetin might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.
Medications changed by the liver (Cytochrome P450 3A4 (CYP3A4) substrates)
Interaction Rating=Moderate Be cautious with this combination.
Some medications are changed and broken down by the liver. Quercetin might change how quickly the liver breaks down these medications. This could change the effects and side effects of these medications.
Medications for diabetes (Antidiabetes drugs)
Interaction Rating=Moderate Be cautious with this combination.
Quercetin might lower blood sugar levels. Taking quercetin along with diabetes medications might cause blood sugar to drop too low. Monitor your blood sugar closely.
Medications for high blood pressure (Antihypertensive drugs)
Interaction Rating=Moderate Be cautious with this combination.
Quercetin might lower blood pressure. Taking quercetin along with medications that lower blood pressure might cause blood pressure to go too low. Monitor your blood pressure closely.
Medications moved by pumps in cells (Organic Anion Transporter 1 (OAT1) Substrates)
Interaction Rating=Moderate Be cautious with this combination.
Some medications are moved in and out of cells by pumps. Quercetin might change how these pumps work and change how much medication stays in the body. In some cases, this might change the effects and side effects of a medication.
Medications moved by pumps in cells (Organic Anion Transporter 3 (OAT3) Substrates)
Interaction Rating=Moderate Be cautious with this combination.
Some medications are moved in and out of cells by pumps. Quercetin might change how these pumps work and change how much medication stays in the body. In some cases, this might change the effects and side effects of a medication.
Medications moved by pumps in cells (Organic anion-transporting polypeptide substrates)
Interaction Rating=Moderate Be cautious with this combination.
Some medications are moved in and out of cells by pumps. Quercetin might change how these pumps work and change how much medication stays in the body. In some cases, this might change the effects and side effects of a medication.
Medications moved by pumps in cells (P-glycoprotein substrates)
Interaction Rating=Moderate Be cautious with this combination.
Some medications are moved in and out of cells by pumps. Quercetin might change how these pumps work and change how much medication stays in the body. In some cases, this might change the effects and side effects of a medication.
Midazolam (Versed)
Interaction Rating=Moderate Be cautious with this combination.
Quercetin might increase how quickly the body breaks down midazolam. Taking quercetin with midazolam might reduce the effects of midazolam.
Mitoxantrone
Interaction Rating=Moderate Be cautious with this combination.
Quercetin might increase levels of mitoxantrone. Taking quercetin and mitoxantrone together might increase the effects and side effects of mitoxantrone.
Pravastatin (Pravachol)
Interaction Rating=Moderate Be cautious with this combination.
Quercetin might decrease how quickly the body gets rid of pravastatin. Taking quercetin with pravastatin might increase the effects and side effects of pravastatin.
Prazosin (Minipress)
Interaction Rating=Moderate Be cautious with this combination.
Quercetin might increase levels of prazosin. Taking quercetin and prazosin together might increase the effects and side effects of prazosin.
Quetiapine (Seroquel)
Interaction Rating=Moderate Be cautious with this combination.
Quercetin might increase levels of quetiapine. Taking quercetin and quetiapine together might increase the effects and side effects of quetiapine.
Sulfasalazine (Azulfidine)
Interaction Rating=Moderate Be cautious with this combination.
Quercetin might increase levels of sulfasalazine. Taking quercetin and sulfasalazine together might increase the effects and side effects of sulfasalazine.
Warfarin (Coumadin)
Interaction Rating=Moderate Be cautious with this combination.
Quercetin might increase the effects that warfarin has on the body. Taking quercetin and warfarin together might increase the effects and side effects of warfarin, which could increase the risk of bruising and bleeding.
Interactions with herbs & supplements
Herbs and supplements that might lower blood sugar: Quercetin might lower blood sugar. Taking it with other supplements with similar effects might lower blood sugar too much. Examples of supplements with this effect include aloe, bitter melon, cassia cinnamon, chromium, and prickly pear cactus.
Interactions with foods
Products
View all products- Quercetin dihydrate 56 mg equiv. quercetin 50 mg
- Aloe barbadensis ext. 2 mg
- Arctium lappa ext. 50 mg
- Gentiana lutea ext. 7.5 mg
- Zingiber officinale ext. 20 mg
- Silica - colloidal anhydrous 215 mg equiv. silica 100 mg
- Glutamine 250 mg
- Zinc citrate dihydrate 46.74 mg equiv. zinc 15 mg
- Calendula officinalis ext. 40 mg
- Curcuma longa ext. 75 mg
- Riboflavin 5-phosphate sodium (Activated B2) 26.67 mg equiv. riboflavin 20 mg
- Calcium pantothenate (Vitamin B5) 21.84 mg equiv. pantothenic acid 20 mg
- Pyridoxine hydrochloride (Vitamin B6) 12.16 mg equiv. pyridoxine 10 mg
- Ascorbic acid (Vitamin C) 50 mg
- d-alpha-Tocopheryl acetate 36.77 mg equiv. vitamin E 25 IU
- Lysine hydrochloride 187.5 mg equiv. lysine 150 mg
- Pectin 50 mg
- Quercetin dihydrate 17 mg equiv. phyto-Phospholipid Complex 50 mg
- Curcumin (Turmeric) 10 mg equiv. phyto-Phospholipid Complex 55.5 mg
- Ascorbic acid (Vitamin C) 25 mg
- Zinc citrate dihydrate 18.7 mg equiv. zinc 6 mg
- Calcium pantothenate (Vitamin B5) 273 mg
- Nicotinamide (Vitamin B3) 50 mg
- Pyridoxal 5-phosphate monohydrate (P5P) 7.8 mg equiv. pyridoxine 5 mg
- Beta-carotene (Carotenoids) 540 µg equiv. vitamin A RE 90 µg RE
- Biotin 250 µg
- Calcium folinate (Activated folate) 136 µg equiv. folinic acid 125 µg
- Quercetin dihydrate 500 mg
- Rutin (Rutoside) 100 mg
- Citrus bioflavonoids extract 50 mg
- Citrus bioflavonoids (Hesperidin) 25 mg
- Ascorbic acid (Vitamin C) 50 mg
- Quercetin 200 mg
- Hordeum vulgare (Barley)
- Green banana starch 250 mg
- Arthrospira platensis (Spirulina)
- Brassica oleracea (Broccoli)
- Punica granatum
- Apple pectin 50 mg
- Macrocystis pyrifera (Ocean kelp)
- Brassica oleracea (leaf & sprout) powder (Kale)
- Spinacia oleracea (Spinach)
- Daucus carota powder (Carrot)
- Brassica oleracea var. viridis
- Palmaria palmata (Dulse)
- Chlorella vulgaris powder
- Apium graveolens (seed) powder
- Petroselinum crispum
- Citrus bioflavonoids extract 150 mg
- Myrciaria dubia (fruit) powder (Camu Camu)
- Malpighia glabra
- Blueberry flavour
- Zingiber officinale
- Kakadu plum powder
- Cocoa powder
- Larix occidentalis (arabinogalactan) (Larch) 250 mg
- Natural flavours
- Pink Himalayan crystal salt
- Ananas comosus (Bromelain) 150 mg
- Origanum vulgare oil
- Thymus vulgaris oil
- Syzygium aromaticum oil
- Mentha x piperita oil
- N-acetyl glucosamine (NAG) 125 mg
- Bacillus coagulans (LactoSpore®) 25 mg
- Stevia rebaubiana
- Zinc citrate 7.5 mg
- Polyphenolic fulvic minerals (Cell Charge™) 50 mg
- Quercetin 100 mg
- Brassica oleracea var. italica powder 250 mg
- Arthrospira platensis (Spirulina) 100 mg
- Cordyceps sinensis 105 mg
- Lentinula edodes 100 mg
- Trametes versicolor 70 mg
- Astragalus membranaceus 100 mg
- Camellia sinensis 500 mg
- Grifola frondosa 125 mg
- Spinacia oleracea (Spinach) 175 mg
- Brassica oleracea (leaf) powder (Kale) 175 mg
- Chlorella vulgaris powder 175 mg
- Nasturtium officinale 160 mg
- Apium graveolens powder 110 mg
- Pleurotus eryngii 100 mg
- Lipase 750 LipU
- Protease 1000 DU
- Ananas comosus (Bromelain) 350 GDU
- Carica papaya (Papain) 40 mg
- L-glutamine 500 mg
- Bacillus coagulans (LactoSpore®) 4 billion CFU
- Lactobacillus rhamnosus 750 million CFU
- Saccharomyces cerevisiae (boulardii) (SB) 500 million CFU
- Taraxacum officinale 100 mg
- Coriandrum sativum 80 mg
- Zingiber officinale 50 mg
- Rosmarinus officinalis 50 mg
- Origanum vulgare powder 50 mg
- Natural flavours
- Stevia rebaubiana ext.
- Eleutherococcus senticosus 100 mg
- Citric acid anhydrous
- Quercetin 100 mg
- Resveratrol 260 mg
- Schisandra chinensis ext. 225 mg
- Brassica oleracea var. italica ext. 300 mg
- Brassica oleracea var. italica ext. 200 mg
- Polygonum cuspidatum
- Curcumin (Turmeric) 300 mg equiv. curcuminoids 285 mg
- Punica granatum ext. 200 mg
- Silybum marianum ext. 100 mg
- N-acetylcysteine (NAC) 200 mg
- Ascorbic acid (Vitamin C) 80 mg
- Citrus bioflavonoids extract 40 mg
- Zinc picolinate equiv. zinc 12 mg
- Selenomethionine equiv. selenium 26 µg
- Methylcobalamin (Activated B12) 4 µg
- Orthosilicic acid (Silica)
- Quercetin dihydrate 100 mg
- Hydrolysed marine collagen 3 g
- Ascorbic acid (Vitamin C) 200 mg
- Silica - colloidal anhydrous 320.85 mg equiv. silica 150 mg
- Haematococcus pluvialis ext. 80 mg
- Aloe barbadensis ext. 50 mg
- Curcuma longa ext. 80 mg
- Eleutherococcus senticosus ext. 33.36 mg
- d-alpha-Tocopheryl acid succinate 41.34 mg equiv. vitamin E 67.5 IU
- L-glutamine 750 mg
- L-glycine 500 mg
- Vaccinium myrtillus juice dry 100 mg
- Quercetin dihydrate 20 mg
- Ascorbic acid (Vitamin C) 1 g
- Retinyl acetate (Vitamin A) 859.75 µg equiv. retinol equivalents 750 µg
- d-alpha-Tocopheryl acetate 21.47 mg equiv. vitamin E 15 IU
- Cyanocobalamin (Vitamin B12) 25 µg
- Zinc ascorbate 5 mg equiv. zinc 785 µg
- Nicotinamide (Vitamin B3) 5 mg
- Pyridoxine hydrochloride (Vitamin B6) 2 mg equiv. pyridoxine 1.6 mg
- Folic acid 40 µg
- Calcium pantothenate (Vitamin B5) 2.5 mg equiv. pantothenic acid 2.29 mg
- Calcium phosphate 34.67 mg equiv. phosphorus 5.5 mg
- Potassium iodide 198.55 µg equiv. iodine 150 µg
- Magnesium carbonate 122.36 mg equiv. magnesium 29.5 mg
- Manganese gluconate 4.55 mg equiv. manganese 500 µg
- Chromium picolinate 96.52 µg equiv. chromium 12 µg
- Cysteine hydrochloride 3.5 mg
- L-aspartic acid 7 mg
- Potassium phosphate - monobasic 96.52 mg equiv. potassium 28 mg equiv. phosphorus 21.95 mg
- Total Calcium 50 mg