Citrus Bioflavonoids
What is it? Overview Usage Side Effects and Warnings

What are Citrus Bioflavonoids?

Citrus fruits are well known for providing ample amounts of vitamin C . But they also supply bioflavonoids, substances that are not required for life but that may improve health. The major bioflavonoids found in citrus fruits are diosmin, hesperidin, rutin, naringin, tangeretin, diosmetin, narirutin, neohesperidin, nobiletin, and quercetin.

This article addresses the first five bioflavonoids listed above. Please see the article Quercetin for information on this supplement. A modified form of rutin, oxerutin , is also discussed in its own article.

Citrus bioflavonoids and related substances are widely used in Europe to treat diseases of the blood vessels and lymph system, including hemorrhoids , chronic venous insufficiency , leg ulcers, easy bruising , nosebleeds , and...

Double-blind trials suggest (but do not prove conclusively) that a micronized combination preparation of diosmin and hesperidin may be helpful for hemorrhoids . 1 Diosmin and hesperidin, as well as the bioflavonoid rutin, may also be helpful for chronic venous insufficiency , a condition in which the veins in the legs begin to weaken. 2 At least one good double-blind trial found diosmin and hesperidin also to be helpful for individuals who develop bruises or nosebleeds easily. 3 Citrus bioflavonoids have also been tried, with some success, for treating lymphedema (arm swelling) following breast cancer surgery . 4

Note: Do not use bioflavonoid combinations containing tangeretin if you are taking tamoxifen for breast cancer.

In addition, highly preliminary evidence...

Safety Issues

Extensive investigations of diosmin and hesperidin have found them to be essentially nontoxic and free of drug interactions. 5 The combination has been given to 50 pregnant women in a research study, without apparent harm to mothers or babies. 6 Some evidence suggests that the bioflavonoid naringen may interact with medications in the calcium channel blocker family, increasing blood levels of the drug. 7 This may necessitate a reduction in drug dosage.

The citrus bioflavonoid tangeretin may reduce the effectiveness of tamoxifen , a drug used to treat breast cancer. 8 One highly preliminary study suggests that some citrus bioflavonoids in the diet of pregnant women might increase the risk of infant leukemia; hesperidin did not produce this effect, and...