Quercetin is a flavonoid extracted from fruit. It supports a healthy immune function and has anti-allergy and antiviral effects. Quercetin also helps support healthy heart function. Ordinarily quercetin is not well absorbed from the intestine, however bromelain enzymes improve absorption.
Each capsule contains the following as active ingredient:
With Bromelain for enhanced absorption.
Store in a cool dry place below 25°C. Keep out of the reach of children.
Quercetin is a naturally occuring flavonoid. Quercetin has antioxidant, antiviral and anti-allergy effects. The antioxidant effect is attributed to the cathechol-B-ring and the location of the hydroxyl substitutions. Quercetin has demonstrated activity against some viruses. This is attributed to quercetin’s ability to reduce the infectivity of viruses and blocking viral replication. Quercetin has also been shown to have a positive effect on the human immune system. Possibly by increasing neutrophil chemotaxis, macrophage phagocytosis, natural killer cell lytic activity, and mitogen-stimulated lymphocyte proliferation. Quercetin has also been shown to have anti-allergy effects attributed to the fact that it may affect mast cell proliferation and secretory granule development.
Adults and children over 12 years of age: Take 2 capsule in the morning and 1 capsule in the evening. This dose can be doubled under the advice of a health care provider. Children under 12 years of age: Take 1 capsule in the morning.
Do not exceed recommended dosages unless on the advice of a health care provider. Do not use this product if you are allergic to any of the ingredients. If you are on any medication or suffering from any medical condition, it is advisable to seek medical advice before starting any new medicine, supplement or remedy.
Side effects may include headache, allergy, gastrointestinal upset and tingling of the extremities. Doses exceeding 9 capsules per day may be damaging to the kidneys.
There are no known contraindications.
Cyclosporin: Quercetin may increase plasma levels and prolong the half-life of cyclosporin. Cytochrome P450 2C8, 2C9, 2D6, 3A4: Preliminary evidence indicates that quercetin may inhibit these enzymes and this may lead to reduced elimination and higher plasma levels of medicines metabolised by these substrates. Some medicines that could be affected include: amiodarone, docetaxel, tretinoins, repaglinide, verapamil, celecoxib, diclofenac, fluvastatin, glipizide, ibuprofen, irbesartan, losartan, phenytoin, piroxicam, tamoxifen, tolbutamide, torsemide, warfarin, amitriptyline, codeine, flecainide, haloperidol, imipramine, metoprolol, ondansetron, paroxetine, risperidone, tramadol, venlafaxine, calcium channel blockers, chemotherapeutic agents antifungals, glucocorticoids, alfentanil, fentanyl, losartan, fluoxetine, midazolam, omeprazole, lansoprazole, propranolol, fexofenadine, amitriptyline, amiodarone, citalopram, sertraline and numerous others. P-glycoprotein substrates: There is preliminary evidence that quercetin inhibits the gastrointestinal P-glycoprotein efflux pump. This may increase the bioavailability and the serum levels of medicines transported by the pump. Medicines transported by the pump include: paclitaxel, diltiazem, cyclosporine, saquinavir, digoxin, chemotherapeutic agents (etoposide, vinblastine, vincristine, vindesine), antifungals (ketoconazole, itraconazole), protease inhibitors (amprenavir, indinavir, nelfinavir), H2 antagonists (cimetidine, ranitidine), verapamil, corticosteroids, erythromycin, fexofenadine, loperamide, quinidine, and others. Quinolone antibiotics: Quercetin might competitively inhibit quinolone antibiotics by binding to the DNA gyrase site on bacteria. Quinolone antibiotics include: ciprofloxacin, levofloxacin, ofloxacin, moxifloxacin, gatifloxacin and others.
Pineapple allergy: Individuals allergic to pineapples should use caution, as bromelain is made from pineapples.
Pregnancy & Breastfeeding
Safety in pregnancy and breastfeeding has not been established.