Quercetin for Cancer: Safety & Side Effects
This page covers safety information for Quercetin. See our complete Quercetin therapy guide →
Side effects and adverse reactions
Quercetin is found in many common foods and is generally considered safe as a supplement. Quercetin has shown few and generally mild side effects in clinical trials and no major adverse effects.1Buonerba C, De Placido P et al. Isoquercetin as an adjunct therapy in patients with kidney cancer receiving first-line sunitinib (quasar): results of a phase I trial. Frontiers in Pharmacology. 2018 Mar 16;9:189; Lu NT, Crespi CM et al. A phase I dose escalation study demonstrates quercetin safety and explores potential for bioflavonoid antivirals in patients with chronic hepatitis C. Phytotherapy Research. 2016 Jan;30(1):160-8.
Drug interactions
There are known drug interactions with this therapy. Interactions with medications and other interventions are complex. Always consult with a healthcare professional before adding any new therapy to your regimen. To learn more about interactions visit one of the trusted resources below:
Interactions with chemotherapy drugs
Quercetin can interact with some chemotherapy drugs.2Azizi E, Fouladdel S et al. Quercetin effects on cell cycle arrest and apoptosis and doxorubicin activity in T47D cancer stem cells. Asian Pacific Journal of Cancer Prevention. 2022 Dec 1;23(12):4145-4154; Zhang P, Zhang J, Zhao L, Li S, Li K. Quercetin attenuates the cardiotoxicity of doxorubicin-cyclophosphamide regimen and potentiates its chemotherapeutic effect against triple-negative breast cancer. Phytotherapy Research. 2022 Jan;36(1):551-561; Li S, Zhao Q et al. Quercetin reversed MDR in breast cancer cells through down-regulating P-gp expression and eliminating cancer stem cells mediated by YB-1 nuclear translocation. Phytotherapy Research. 2018 Aug;32(8):1530-1536; Wang Y, Yu H et al. Targeted delivery of quercetin by nanoparticles based on chitosan sensitizing paclitaxel-resistant lung cancer cells to paclitaxel. Materials Science and Engineering. C, Materials for Biological Applications. 2021 Feb;119:111442; Koren Carmi Y, Mahmoud H et al. Flavonoids restore platinum drug sensitivity to ovarian carcinoma cells in a phospho-ERK1/2-dependent fashion. International Journal of Molecular Sciences. 2020 Sep 7;21(18):6533; Zhao Q et al. Quercetin reversed MDR in breast cancer cells through down-regulating P-gp expression and eliminating cancer stem cells mediated by YB-1 nuclear translocation. Phytotherapy Research. 2018 Aug;32(8):1530-1536; Zhao Q et al. Quercetin reversed MDR in breast cancer cells through down-regulating P-gp expression and eliminating cancer stem cells mediated by YB-1 nuclear translocation. Phytotherapy Research. 2018 Aug;32(8):1530-1536; Manthalkar L, Ajazuddin, Bhattacharya S. Evidence-based capacity of natural cytochrome enzyme inhibitors to increase the effectivity of antineoplastic drugs. Discover. Oncology. 2022 Dec 26;13(1):142; Xu W, Xie S, Chen X, Pan S, Qian H, Zhu X. Effects of quercetin on the efficacy of various chemotherapeutic drugs in cervical cancer cells. Drug Design, Development and Therapy. 2021 Feb 15;15:577-588. Be sure to let your oncologist know that you are taking quercetin if you are planning treatment or in treatment.
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References