Antioxidant Supplements Before Surgery and With Kidney or Liver Disease

Urgent first

Call 911 for heavy bleeding that will not stop. For yellow skin or eyes, dark urine, severe stomach pain or persistent vomiting while taking any supplement, contact a doctor urgently. For curcumin, NCCIH lists fatigue, nausea, poor appetite, dark urine or jaundice as possible signs of liver damage and says to stop the product and talk with your provider. [1] Do not stop a prescribed medicine on your own; ask your prescriber.

Before surgery

NCCIH says that if you are going to have surgery, certain dietary supplements may increase the risk of bleeding or affect your response to anesthesia, and to tell your providers about all supplements "as far in advance of the operation as possible." [2]

Antioxidant-specific points from the sources we read:

• Vitamin E: high doses may reduce the blood's ability to clot and may interact with anticoagulant or antiplatelet medicines. [3] MedlinePlus adds that high doses of alpha-tocopherol supplements might raise the risk of bleeding in the brain (hemorrhagic stroke). [4]
• CoQ10: may interact with the blood thinner warfarin and with insulin. [5]
• Vitamin C: NCCIH notes it can worsen iron overload in hemochromatosis. [3]
• Herbal products in general: a 2001 JAMA review of eight common herbs found bleeding concerns for garlic, ginkgo and ginseng; it did not review the antioxidant supplements above, and it is old. [6]

How long before surgery to pause a supplement is not described in the sources we read, so no timing is given here. Your surgical team and pharmacist decide. See Supplements Before Surgery for the safety hub.

Kidney conditions

NCCIH says kidney disease has been linked to some dietary supplements, and that people with or at risk of kidney disease should have a health care provider closely monitor supplement use. [7] The evidence we read:

Lower albuminuria is a lab marker, not proof of slower kidney failure. Official upper-intake figures for people with reduced kidney function were not found in the sources we read. Proper evidence not found: we looked for guidance specific to antioxidants in advanced kidney disease and found none usable. See also minerals, supplements and kidney disease and quercetin side effects and kidney cautions.

Liver conditions and liver injury reports

NCCIH says acute liver damage from dietary supplements is rare but more cases are being reported, and can be severe or fatal. [2]

• Green tea extract: NCCIH says liver injury has been reported with green tea products, mainly extracts in tablet or capsule form, and that people with a particular immune-related gene variant seem especially susceptible. [10]
• Curcumin: NCCIH says highly bioavailable curcumin formulations may harm the liver and liver damage has been reported. [1] An Italian phytovigilance analysis described seven cases of acute hepatitis linked to high-bioavailability, high-dose products. [11] A series of 11 turmeric-supplement hepatitis cases urges a full supplement history when liver injury is investigated. [12]
• Berberine: a 2017 toxicity review says berberine and barberry could induce jaundice in a dose-dependent manner and should be used with caution in pregnancy, in newborns and in G6PD deficiency. [13]

If you already have liver disease, whether these supplements are safe for you is not described in the sources we read; ask your liver or primary care clinician. See Liver Safety & Supplements, Green Tea Extract and EGCG and Curcumin Safety.

Bring to your clinician

• A list of every supplement with its label, including combination products.
• Your upcoming procedure date, kidney or liver test results, and all medicines.