- patients with proven hypersensitivity or allergic reaction to quercetin - patients with known chronic kidney disease with estimated creatinine clearance < 50 ml/minute or need for dialysis - patients who are severely hypotensive defined as needing hemodynamic pressors to maintain blood pressure - patients with moderate or severe thrombocytopenia (platelet count <100 × 10⁹/l); - pregnant patients - patients declining to participate

- patients with proven hypersensitivity or allergic reaction to quercetin - patients with known chronic kidney disease with estimated creatinine clearance < 50 ml/minute or need for dialysis - patients who are severely hypotensive defined as needing hemodynamic pressors to maintain blood pressure - patients with moderate or severe thrombocytopenia (platelet count <100 × 10⁹/l); - pregnant patients - patients declining to participate