skip to Main Content


A flavonoid extracted from fruit. It supports healthy immune function and has anti-allergy and antiviral effects. Quercetin also reduces the risk of death from coronary artery disease. Ordinarily quercetin is not well absorbed from the intestine, but bromelain enzymes are included in SOLAL Quercetin for improved quercetin absorption and effectiveness.


Buy product


Quercetin is a flavonoid antioxidant extracted from fruit. It supports healthy immune function and maintains good health especially during exercise. Ordinary quercetin is not well absorbed from the intestine, however SOLAL® adds bromelain enzymes to improve absorption.

Product Composition

Each capsule contains the following active ingredients:

Quercetin 267mg
Bromelain 35mg

Inactive ingredients: Hypromellose (cellulose) vegetarian capsule shell (gelatine free), microcrystalline cellulose, magnesium stearate (vegetarian – flow agent), magnesium silicate, silicon dioxide and colloidal silicon dioxide.

Contains plant extracts and natural fillers, with no colourants added – therefore the colour of the capsule contents may vary slightly from batch to batch.


Storage Instructions

Store in a cool dry place below 25°C. Keep out of reach of children.

Pharmacological Action

Dietary quercetin glycosides are hydrolysed in the intestine to produce the aglycone, and also undergo deglycosidation by enterobacteria. The aglycone is then conjugated to glucuronides or sulphates for absorption. Quercetin is present in the plasma glucuronides, sulphates and O-methylated derivatives, with only small quantities of the aglycone. Quercetin has antioxidant, anti-inflammatory and cardio-protective effects. The antioxidant effect is attributed to the cathechol-B ring and the location of the hydroxyl substitutions. The antioxidant effect is due to its ability to be converted to substances that release reactive oxygen species. The anti-inflammatory effects of quercetin are due to its inhibition of the production and activity of leukotrienes and prostaglandins, and inhibition of histamine release by basophils and mast cells. Animal studies indicate that quercetin inhibits cox-2 enzymes and also NF-kB which controls expression of genes encoding pro-inflammatory cytokines. Quercetin has demonstrated activity against retroviruses, herpes simplex, polio, parainfluenza and respiratory syncytial viruses. This is attributed to quercetin’s ability to reduce the infectivity of viruses and block 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’s anti-carcinogenic effects have been attributed to the following mechanisms, antioxidant effects, inhibition of cell proliferation, cell cycle arrest, induction of apoptosis, promotion of cell differentiation, and inhibition of angiogenesis. 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. Quercetin consumption exhibited an inhibitory effect on the development of aortic atherosclerotic lesions and on arthrogenic modifications of LDL injury by inhibiting lipoprotein oxidation or by directly protecting cells from oxidised low density lipoproteins.

Dosage Directions

Take 2 capsules in the morning and 1 capsule in the evening. This dose can be doubled under the advice of a healthcare provider.

Children under 12 years of age:
Take 1 capsule in the morning.

Product Warnings

Do not use this product if you are hypersensitive (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. Do not exceed recommended dosages unless on the advice of a healthcare practitioner. This medicine has not been evaluated by the Medicines Control Council. This medicine is not intended to diagnose, treat, cure or prevent any disease.

Take special care with Quercetin if you suffer from an allergy to pineapples, as Bromelain is made from pineapples.

Side Effects

Side effects include headache, allergy, gastrointestinal upset and tingling of the extremities. Doses exceeding 6 capsules per day may be damaging to the kidney.


There are no known contraindications.


Cyclosporine: Quercetin increases plasma levels and prolongs the half-life of cyclosporine.
Cytochrome P450 2C8, 2C9, 2D6, 3A4: Preliminary evidence indicated that quercetin inhibits 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 the quercetin inhibits the gastrointestinal P-glycoprotein efflux pump. This may increase the bioavailability and the serum levels of drugs 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, zexofenadine, loperamide, quinidine, and others.
Quinolone antibiotics: Quercetin might competitively inhibit quinolone antibiotics by binding to the DNA gyrase site on bacteria. Quinolones include: ciprofloxacin, levofloxacin, ofloxacin, moxifloxacin, gatifloxacin and others.

Special Precautions

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.

Your opinion matters to us. Please share your comments on our Facebook page.

Back To Top