Quercetin for Dogs: Benefits, Dose, and How It Works

Quercetin is a bioflavonoid with the strongest evidence base of any natural compound for managing allergic disease in dogs. It works through mast cell stabilization, cytokine suppression, and COX/LOX inhibition — addressing multiple arms of the allergic response simultaneously.

What quercetin does

• Mast cell stabilization: Reduces histamine release triggered by allergen exposure — the root of allergic itch and inflammation
• IL-4 and IL-13 suppression: Inhibits the cytokines that polarize the immune system toward the allergic Th2 response
• COX-2 and LOX inhibition: Broad anti-inflammatory activity relevant to joint disease as well as allergy
• Antioxidant activity: Neutralizes reactive oxygen species that drive cellular inflammation

Why bromelain is essential

Quercetin has poor oral bioavailability without a co-factor. Bromelain (a pineapple-derived proteolytic enzyme) enhances quercetin absorption by 3–10x and provides independent prostaglandin suppression. Any quercetin supplement without bromelain is delivering a fraction of its potential effect.

Therapeutic dose by dog weight

• Under 20 lbs: 100–150mg quercetin daily
• 20–40 lbs: 150–300mg quercetin daily
• 40–70 lbs: 300–500mg quercetin daily
• 70–100 lbs: 400–600mg quercetin daily

Products with a single dose recommendation for all dog sizes are either severely underdosing large dogs or overdosing small ones.

Timeline

Anti-inflammatory effects begin within 2–4 weeks. Full immune-regulatory effect (T cell polarization changes, mast cell density reduction) develops over 6–10 weeks of consistent use. Most allergic dogs show meaningful improvement by week 6–8.

Safety

Well-tolerated at therapeutic doses. Take with food if GI sensitivity occurs. Dogs on anticoagulants or with renal disease should have veterinary consultation before high-dose supplementation.