Safety Profile
Overall safety rating: Generally Safe
Quercetin Side Effects & Safety
This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer
Potential Side Effects
- Generally well-tolerated at recommended doses
- GI discomfort (nausea, stomach cramps) at higher doses
- Headache reported by some users, particularly at doses above 1000mg
- May cause tingling or numbness in extremities in rare cases
Drug & Supplement Interactions
- Cyclosporine — quercetin may increase blood levels of cyclosporine by inhibiting CYP3A4
- Blood thinners (warfarin, aspirin) — quercetin has mild antiplatelet activity and may enhance anticoagulant effects
- Fluoroquinolone antibiotics — quercetin may interfere with their antibacterial activity
- Quercetin may interact with medications metabolized by CYP3A4, CYP1A2, and CYP2C9 enzymes
Maximum Dose
Do not exceed: 1500mg/day (higher doses may cause GI discomfort and headache)
References
- Justice JN, Nambiar AM, Tchkonia T, et al. (2019). Senolytics in idiopathic pulmonary fibrosis: Results from a first-in-human, open-label, pilot study. EBioMedicine. DOI PubMed
- Serban MC, Sahebkar A, Zanchetti A, et al. (2016). Effects of quercetin on blood pressure: a systematic review and meta-analysis of randomized controlled trials. Journal of the American Heart Association. DOI PubMed
- Riva A, Ronchi M, Petrangolini G, Bosisio S, Allegrini P (2019). Improved oral absorption of quercetin from quercetin Phytosome, a new delivery system based on food grade lecithin. European Journal of Drug Metabolism and Pharmacokinetics. DOI PubMed