Quercetin: What it is and how it can help

Want fewer sniffles or less day-to-day inflammation? Quercetin is a plant flavonoid found in onions, apples, berries and green tea that many people use for allergy relief and antioxidant support. It works differently than antihistamines: quercetin helps stabilize mast cells and may reduce the release of histamine, the chemical that causes sneezing and itching.

People reach for quercetin for seasonal allergies, mild inflammation after exercise, or to add antioxidant protection to their diet. It’s not a miracle cure, but several clinical studies report modest improvements in allergy symptoms and markers of inflammation when quercetin is used regularly.

What quercetin does and where to get it

Whole foods are a good place to start: red onions, capers, apples, citrus peels, grapes, and berries all contain quercetin. If you want stronger effects, supplements are common. Typical products use quercetin dihydrate or quercetin complexed with bromelain. Bromelain (an enzyme from pineapple) or vitamin C can boost absorption and may enhance the overall effect.

Expect subtle benefits. For allergies, people often report fewer sneezes, less watery eyes, and calmer nasal irritation after a few weeks. For general inflammation and antioxidant support, quercetin can be part of a broader plan that includes diet, sleep, and activity.

Dosage, safety, and what to watch for

Common supplement doses range from 250 mg to 1,000 mg per day, usually split into two doses. Many users start at 250–500 mg daily and increase if needed. Short-term use at these doses is generally well tolerated. Side effects can include mild stomach upset or headache at higher doses.

Quercetin can interact with some medications. It may affect how the body metabolizes drugs processed by liver enzymes (CYP pathways). That matters for people on blood thinners like warfarin, certain immunosuppressants, or drugs heavily metabolized by CYP3A4/CYP2C9. If you’re pregnant, breastfeeding, or taking prescription meds, check with your healthcare provider before starting quercetin.

Practical tips: choose a supplement from a reputable brand that lists the quercetin form and purity. Taking quercetin with food and vitamin C or a product that includes bromelain can improve absorption. Give it a few weeks to notice effects—this isn’t an instant antihistamine—but many people see steady improvements when used consistently.

Want more real-world advice? Browse our guides and product pages at NorthwestPharmacy.SU for comparisons, dosing tips, and safety notes so you can pick the right option for your needs.